Robert B. Catell
 
                              Employment Agreement
 
     THIS AGREEMENT by and between KeySpan  Corporation,  a New York Corporation
(the "Company"),  and Robert B. Catell (the  "Executive"),  dated as of February
24, 2005.
 
 
                           W I T N E S S E T H   T H A T
 
     WHEREAS, the Company wishes to provide for the employment by the Company of
the Executive,  and the Executive wishes to serve the Company, in the capacities
and on the term and conditions set forth in this Agreement;
 
     NOW, THEREFORE, it is hereby agreed as follows:
 
1.   EMPLOYMENT PERIOD.
 
     (a) Subject to Section 4 of this  Agreement,  the Company  shall employ the
Executive,  and  the  Executive  shall  serve  the  Company,  on the  terms  and
conditions set forth in this Agreement, for the period (the "Employment Period")
beginning on January 1, 2005 and ending on July 31, 2006. The Company may extend
the term of this Agreement for an additional period of time with the approval of
the KeySpan Board of Directors (the "Board").
 
     (b)  In  the  event  that  during  the  term  of  this  agreement,  KeySpan
consummates  a Change of Control (as such term is defined in the KeySpan  Senior
Executive  Change  of  Control  Severance  Plan),  or enters  into a  definitive
agreement  relating to a transaction  which, if consummated,  would constitute a
Change of Control, Executive's Employment Period will be extended until a period
of twenty four (24)  months  after the  consummation  of such Change of Control;
provided,  however, that if such definitive agreement is terminated or the Board
determines  that a Change of Control  will not be  consummated,  the  Employment
Period shall end on the later of (i) thirty (30) days following the  termination
of such definitive  agreement or the determination by the Board that such Change
of Control will not be consummated and (ii) July 31, 2006. The period  beginning
with the earlier of (x) the  consummation of a Change of Control or (x) the date
that KeySpan enters into a definitive agreement relating to a transaction which,
if  consummated,  would  constitute a Change of Control and ending on the second
anniversary of the date such Change of Control is consummated  shall be referred
to as the "Protection Period".
 
2.   POSITION AND DUTIES.
 
     (a) During the Employment Period, the Executive shall serve as Chairman and
Chief Executive Officer of the Company, and as a member of the Board.  Executive
will remain the Chief Executive Officer until a date determined by the Board, at
which time the Board may separate the two titles and  Executive  will remain the
Chairman of the Board.
 
 
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     (b) During the Employment  Period, and excluding any period of vacation and
sick leave to which the Executive is entitled,  the  Executive  shall devote his
full  business  time and best efforts to the business and affairs of the Company
and, to the extent necessary to discharge the  responsibilities  assigned to the
Executive  under this Agreement,  use the Executive's  reasonable best effort to
carry out such  responsibilities  faithfully  and  efficiently.  It shall not be
considered a violation of the foregoing for the Executive to serve on corporate,
industry, civic or charitable boards or committees.
 
     (c) The Executive's  services shall be performed primarily at the Company's
headquarters  in the five  boroughs of New York City,  or in Nassau,  Suffolk or
Westchester Counties of New York.
 
3.   COMPENSATION.
 
     (a) BASE SALARY.  During the Employment Period, the Executive shall receive
an annual base salary (the  "Annual Base  Salary") of not less than  $1,036,000,
payable in accordance with the Company's regular payroll practice for its senior
executives, as in effect from time to time. The salary level shall be subject to
review as part of the annual review of executive compensation by the Board.
 
     (b) INCENTIVE  COMPENSATION.  During the Employment  Period,  the Executive
shall participate in short-term incentive  compensation plans ("Annual Incentive
Compensation")   and/or  long-term  incentive   compensation  plans  ("Long-Term
Incentive  Compensation")  providing him with the  opportunity to earn an annual
incentive and long-term incentive  compensation at a level subject to review and
approval  of the Board as part of the annual  compensation  review and  approval
process.
 
     (c) In the  event  that the  Board of  Directors  elects  to  separate  the
Chairman and the Chief  Executive  Officer title into two  positions,  the Board
shall  review  the  Executive's  total  compensation  package  and shall  make a
determination  with  respect  to  the  Executive's  level  of  Annual  Incentive
Compensation and Long Term Incentive Compensation.
 
(d)  OTHER BENEFITS.
 
     (i)  The Executive shall be entitled to the benefits  described in Appendix
          A hereto (the "SERP").
 
     (ii) During the Employment  Period, the Company shall provide the Executive
          with life insurance coverage (the "Life Insurance Coverage") providing
          a death benefit to such  beneficiary or beneficiaries as the Executive
          may designate in the amount  provided to him as the Chairman and Chief
          Executive Officer, or Chairman,  under the Flexible Premium Adjustable
          Life Insurance  Program of KeySpan  Corporation or such greater amount
          as may be provided under the Program from time to time.
 
 
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     (iii)In addition,  and without  limiting the  generality of the  foregoing,
          during the Employment  Period and thereafter:  (A) the Executive shall
          be entitled to participate in all  applicable  incentive,  savings and
          retirement plans,  practices,  policies and programs of the Company to
          the same extent as other senior  executives  (or,  where,  applicable,
          retired  senior  executives)  of the  Company;  and (B) the  Executive
          and/or the Executive's  family,  as the case may be, shall be eligible
          for  participation  in, and shall  receive  all  benefits  under,  all
          applicable  welfare  benefit plans,  practices,  policies and programs
          provided  by  the  Company,  other  than  severance  plans,  practice,
          policies and  programs but  including,  without  limitation,  medical,
          prescription,  dental, disability,  salary continuance,  employee life
          insurance, group life insurance,  accidental death and travel accident
          insurance  plans and  programs,  to the same  extent  as other  senior
          executives  of the company.  After the  Employment  Period,  Executive
          shall be entitled to  participate  in all plans  applicable to retired
          senior executives of the Company.
 
     (e)  PERQUISITES.  During the  Employment  Period,  the Executive  shall be
entitled to receive  perquisites  on the same terms and  conditions  as those he
received  from KeySpan  Corporation  immediately  before the  Employment  Period
including,  but not limited, to the KeySpan Executive Leased Vehicle Program and
the KeySpan Senior Executive Perquisite Program.
 
4.   TERMINATION OF EMPLOYMENT.
 
     (a)  DEATH  OR  DISABILITY.  The  Executive's  employment  shall  terminate
automatically  upon the  Executive's  death during the  Employment  Period.  The
Company shall be entitled to terminate the Executive's employment because of the
Executive's Disability during the Employment Period. "Disability" means that (i)
the  Executive  has  been  unable,  for a period  of one  hundred  eighty  (180)
consecutive  business  days,  to  perform  the  Executive's  duties  under  this
Agreement,  as a result of  physical  or mental  illness or  injury,  and (ii) a
physician  selected  by the  Company  or its  insurers,  and  acceptable  to the
Executive or the  Executive's  legal  representative,  has  determined  that the
Executive's  incapacity is total and permanent. A termination of the Executive's
employment by the Company for Disability  shall be communicated to the Executive
by written notice,  and shall be effective on the 30th day after receipt of such
notice by the Executive (the "Disability  Effective Date"), unless the Executive
returns to full-time performance of the Executive's duties before the Disability
Effective Date.
 
     (b)  BY THE COMPANY.
 
     (i) The  Company  may  terminate  the  Executive's  employment  during  the
Employment  Period for Cause or without Cause.  "Cause" means  conviction of the
Executive of a felony under the laws of the United  States or gross  misconduct,
which is willful and results in material and demonstrable damage to the business
or  reputation  of the  Company.  No act or  failure  to act on the  part of the
Executive  shall be  considered  "willful"  unless it is done,  or omitted to be
 
 
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done,  by the  Executive  in bad faith or  without  reasonable  belief  that the
Executive's action or omission was in the best interests of the Company. Any act
or failure to act that is based upon  authority  given  pursuant to a resolution
duly adopted by the Board,  or the advice of counsel for the  Company,  shall be
conclusively  presumed to be done,  or omitted to be done,  by the  Executive in
good faith and in the best interests of the Company.
 
     (ii) A  termination  of the  Executive's  employment  for  Cause  shall  be
effected in accordance with the following procedures. The Company shall give the
Executive written notice ("Notice of Termination for Cause") of its intention to
terminate  the  Executive's  employment  for Cause,  setting forth in reasonable
detail the specific  conduct of the  Executive  that it considers to  constitute
Cause and the specific  provision(s)  of this Agreement on which it relies,  and
stating the date,  time and place of the Special  Board  Meeting for Cause.  The
"Special  Board  Meeting for Cause" means a meeting of the Board called and held
specifically  for the purpose of considering  the  Executive's  termination  for
Cause,  that takes  place not less than ten (10) and not more than  twenty  (20)
business days after the Executive  receives the Notice of Termination for Cause.
The Executive shall be given an opportunity, together, with counsel, to be heard
at the Special Board Meeting for Cause.  The  Executive's  termination for Cause
shall be effective when and if a resolution is duly adopted at the Special Board
Meeting for Cause by affirmative vote of a majority of the entire  membership of
the Board, excluding employee directors,  stating that in the good faith opinion
of the Board, the Executive is guilty of the conduct  described in the Notice of
Termination for Cause, and that conduct constitutes Cause under this Agreement.
 
     (iii) A termination of the  Executive's  employment  without Cause shall be
effected in accordance with the following procedures. The Company shall give the
Executive  written  notice  ("Notice  of  Termination  without  Cause")  of  its
intention to terminate the  Executive's  employment  without Cause,  stating the
date,  time and place of the Special Board Meeting  without Cause.  The "Special
Board  Meeting  Without  Cause"  means a meeting  of the Board  called  and held
specifically for the purpose of considering the Executive's  termination without
Cause,  that takes  place not less than ten (10) and not more than  twenty  (20)
business days after the  Executive  receives the Notice of  Termination  without
Cause. The Executive shall be given an opportunity, together with counsel, to be
heard at the Special Board Meeting without Cause.  The  Executive's  termination
without Cause shall be effective when and if a resolution is duly adopted at the
Special Board Meeting  without  Cause by  affirmative  vote of a majority of the
entire membership of the Board,  excluding employee directors,  stating that the
Executive is terminated without Cause.
 
     (c)  GOOD REASON.
 
     (i) The Executive may terminate  employment for Good Reason or without Good
Reason. Prior to the consummation of a Change of Control, "Good Reason" means:
 
     (A)  the  assignment  to the  Executive of any duties  inconsistent  in any
          respect with paragraph (a) of Section 2 of this Agreement, the failure
          to provide the Executive with the titles  required by paragraph (a) of
          Section 2 of this  Agreement  or with  duties  commensurate  with such
          titles,  as and when  required  by said  paragraph  (a),  or any other
 
 
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          action,  or failure to take action,  by the Company,  the Board or the
          shareholders  of the Company by the Company that results in diminution
          in the  Executive's  position as either  Chairman and Chief  Executive
          Officer or Chairman,  authority,  titles,  duties or responsibilities,
          other than an isolated,  insubstantial and inadvertent  action that is
          not taken in bad faith and is remedied by the Company  promptly  after
          receipt of notice thereof from the Executive;
 
     (B)  any  failure to comply with any other  provision  of Section 3 of this
          Agreement,  other than an isolated,  insubstantial inadvertent failure
          to comply with a provision of Section 3 of this  Agreement that is not
          taken in bad faith  and is  remedied  by the  Company  promptly  after
          receipt of notice thereof from the Executive;
 
     (C)  any  requirement  by the  Company  that the  Executive's  services  be
          rendered primarily at a location or locations other than that provided
          for in paragraph (c) of Section 2 of this Agreement;
 
     (D)  any purported termination of the Executive's employment by the Company
          for a reason or in a manner not expressly permitted by this Agreement;
 
     (E)  any failure by the Company to comply with  paragraph (c) of Section 12
          of this Agreement; or
 
     (F)  any other  substantial  breach of this  Agreement  by the Company that
          either is not taken in good faith or is not  remedied  by the  Company
          promptly after receipt of notice thereof from the Executive.
 
     On or following  the  consummation  of a Change of Control,  "Good  Reason"
means:
 
     (A)  Executive no longer serves as a full-time  executive and member of the
          board of directors of the parent entity  resulting  from the Change of
          Control;
 
     (B)  any  decrease in  Executive's  Annual Base Salary or Annual  Incentive
          Compensation  or other benefits as provided  under  paragraphs (d) and
          (e) of Section 3 of this agreement;
 
     (C)  any requirement that the Executive's services be rendered primarily at
          a location or locations  other than that provided for in paragraph (c)
          of Section 2 of this Agreement; or
 
     (D)  Executive's  notice of termination of employment within the thirty-day
          period  following  the first  anniversary  of the  Change of  Control;
          provided Executive's employment actually terminates within such 30 day
          period.
 
 
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<PAGE>
 
 
     (ii) A termination  of employment by the Executive for Good Reason shall be
effectuated  by giving the Company  written notice  ("Notice of Termination  for
Good  Reason")  of the  termination,  setting  forth in  reasonable  detail  the
specific  conduct of the Company that  constitutes  Good Reason and the specific
provision(s) of this Agreement on which the Executive  relies.  A termination of
employment  by the  Executive  for Good Reason  shall be  effective on the fifth
business day following the date when the Notice of  Termination  for Good Reason
is given,  unless the notice  sets  forth a later date  (which  date shall in no
event be later than 30 days after the notice is given).
 
     (iii) A termination of the Executive's  employment by the Executive without
Good  Reason  shall be  effected  by giving the  Company  written  notice of the
Termination.
 
     (d) NO  WAIVER.  The  failure  to set forth any fact or  circumstance  in a
Notice of  Termination  for Cause,  A Notice of  Termination  without Cause or a
Notice of Termination for Good Reason shall not constitute a waiver of the right
to assert,  and shall not preclude the party giving notice from asserting,  such
fact or  circumstance  is an attempt to enforce any right under or  provision of
this Agreement.
 
     (e) DATE OF TERMINATION.  The "Date of  Termination"  means the date of the
Executive's  death,  the  Disability  Effective  Date,  the  date on  which  the
termination  of the  Executive's  employment by the Company for Cause or without
Cause or by the Executive for Good Reason is effective, or the date on which the
Executive gives the company notices of a termination of employment  without Good
Reason or Retirement, as the case may be.
 
5.   OBLIGATIONS OF THE COMPANY UPON TERMINATION.
 
     (a) BY THE COMPANY OTHER THAN FOR CAUSE OR DISABILITY OTHER THAN DURING THE
PROTECTION  PERIOD;  BY THE  EXECUTIVE  FOR GOOD  REASON  OTHER THAN  DURING THE
PROTECTION  PERIOD.  (i) If, during the Employment Period (other than during the
Protection  Period),  the Company terminates the Executive's  employment,  other
than for Cause or Disability,  or the Executive  terminates  employment for Good
Reason, the Company shall
 
          (A) pay to the Executive, in a single lump sum in cash within ten (10)
     days of the Date of Termination (to the extent permitted under Section 409A
     of the Internal Revenue Code of 1986 as amended or otherwise 6 months after
     the Date of  Termination),  (I) the  Accrued  Obligations  (as  defined  in
     Section 5(b) below), and (II) the aggregate amount of the salary and Annual
     Incentive  Compensation  that he would  have  received  if he had  remained
     employed  for the  Severance  Period (as defined  below)(assuming  that the
     Annual Incentive Compensation for such period would have equaled the higher
     of (X) the  target  amounts  of such  Incentive  Compensation  as in effect
     immediately  before  the Date of  Termination,  (Y) the  average  amount of
     Annual  Incentive  Compensation  for the three most recent years before the
     Date of Termination,  or (Z) the Annual Incentive  Compensation received by
     Executive for the year  preceding the year in which the Date of Termination
     occurred); (B) cause the Executive to continue to accrue benefits under the
     SERP during the Severance  period  subject to the right of the Executive to
     receive  such  additional  benefits  accrual in lump sum, as  specified  in
     Clause (A) of paragraph (a)(i) of Section 5 above;
 
 
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          (C) continue to provide the Executive with Life Insurance Coverage and
     the benefits set forth in Clause (B) of paragraph (d)(iii) of Section 3, as
     if he had  remained  employed  by the Company  pursuant  to this  Agreement
     during  the  Severance  Period and then  retired  (at which time he will be
     treated as eligible for all retiree  welfare  benefits  and other  benefits
     provided to retired senior executives,  as set forth in Section 3(d)(iii));
     PROVIDED,  that to the extent such benefits cannot be provided  pursuant to
     the plan or program  maintained  by the  Company  for its  executives,  the
     Company  shall  provide  such  benefits  outside such plan or program at no
     additional  cost (including  without  limitation tax cost) to the Executive
     and his family  and  PROVIDED,  further,  that  during any period  when the
     Executives is eligible to receive welfare benefits of the type described in
     clause   (B)  of   paragraph   (d)(iii)   of   Section   3  under   another
     employer-provided  plan, the corresponding benefits provided by the Company
     under this  paragraph  (a)(i) of Section 5 may be made  secondary  to those
     provided under such other plan.  For purposes of such continued  accrual of
     benefits under the SERP, the Executive shall be considered to have remained
     employed  for  a  period  equal  to  the  Severance  Period,   with  annual
     compensation  equal to (x) the  amount  required  to be paid  under  clause
     (A)(II) of this section 5, divided by (y) the number of years and fractions
     thereof in the Severance Period, and then to have terminated his employment
     and retired; and
 
          (D)  provide  that any  restricted  stock  outstanding  on the Date of
     Termination  shall be fully  vested as of the Date of  Termination  and all
     options  outstanding on the Date of  Termination  shall be fully vested and
     exercisable  through the end of their respective  terms,  without regard to
     the  termination of the Executive's  Employment and all performance  shares
     shall be deemed fully vested at target.
 
     (ii) For purposes of this Agreement:  (A) the "Severance Period" shall mean
the period from the Date of Termination through the end of the Employment Period
(other than during the Protection Period);
 
     (b) DEATH OR  DISABILITY.  If the  Executive's  employment is terminated by
reason of the Executive's death or Disability during the Employment  Period, the
Company shall pay to the Executive or, in the case of the Executive's  death, to
the Executive's designated  beneficiaries (or, if there is not such beneficiary,
to the Executive's estate or legal representative), in a lump sum in cash within
ten (10) days  after the Date of  Termination  (to the  extent  permitted  under
Section 409A of the Internal  Revenue Code of 1986 as amended or  otherwise,  no
later than 6 months after Date of Termination), the sum of the following amounts
(the  "Accrued  Obligations"):  (1) any portion of the  Executive's  Annual Base
Salary through the Date of Termination that has not yet been paid; (2) an amount
representing   the  Annual  Incentive   Compensation  and  Long-Term   Incentive
Compensation  for the period that includes the Date of Termination,  computed by
assuming that the amount of all such  Incentive  Compensation  would be equal to
the target amount of such Incentive Compensation as in effect immediately before
 
 
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the  Date of  Termination,  and  multiplying  that  amount  by a  fraction,  the
numerator  of which is the  number of days in such  period  through  the Date of
Termination,  and the  denominator  of which is the total  number of days in the
relevant  performance  period; (3) any compensation  previously  deferred by the
Executive  (together with any accrued interest or earnings thereon) that has not
yet been paid;  and (4) any Annual  Incentive  Compensation  and cash  Long-Term
Incentive  Compensation actually earned but not yet paid for performance periods
ending on or before the Date of  Termination,  accrued but unpaid  vacation pay,
and the Company shall have no further  obligations under this Agreement,  except
as specified in Sections 3(d) above and Section 6 below.
 
     (c) BY THE COMPANY FOR CAUSE,  BY THE EXECUTIVE OTHER THAN FOR GOOD REASON.
If the Executive's  employment is terminated by the Company for Cause during the
Employment  Period,  the Company  shall pay the Executive the Annual Base Salary
through the Date of Termination  and the amount of any  compensation  previously
deferred  by the  Executive  (together  with any  accrued  interest  or earnings
thereon),  in each case to the extent not yet paid  within ten (10) days (to the
extent  permitted  under  Section 409A of the  Internal  Revenue Code of 1986 as
amended or otherwise, no later than 6 months after the Date of Termination), and
the Company shall have no further  obligations  under this Agreement,  except as
specified in Section 6 below. If the Executive voluntarily terminates employment
during the Employment Period,  other than for Good Reason, the Company shall pay
the Accrued  Obligations  to the Executive in a lump sum in cash within ten (10)
days of the Date of Termination  (to the extent  permitted under Section 409A of
the Internal Revenue Code of 1986 as amended or otherwise no later than 6 months
after  the  Date  of  Termination),  and  the  Company  shall  have  no  further
obligations  under this  Agreement,  except as  specified  in  paragraph  (d) of
Section 3 above and Section 6 below.
 
     (d) BY THE COMPANY OTHER THAN FOR CAUSE OR DISABILITY DURING THE PROTECTION
PERIOD; BY THE EXECUTIVE FOR GOOD REASON DURING THE PROTECTION  PERIOD.  (i) If,
during the Employment Period and during the Protection  Period,  (x) the Company
terminates the Executive's  employment,  other than for Cause or Disability,  or
the  Executive  terminates  employment  for Good  Reason  and (y) the  Change of
Control is consummated, the Company shall
 
          (A) pay to the  Executive in a single lump sum in cash within ten (10)
     days of the Date of Termination (to the extent permitted under Section 409A
     of the Internal Revenue Code of 1986 as amended or otherwise 6 months after
     the Date of  Termination) an amount equal to the sum of (a) the Executive's
     Annual  Base  Salary  through  the Date of  Termination  to the  extent not
     theretofore  paid,  (b) the product of (x) the higher of (i) the average of
     the Annual Incentive Compensation received by the Executive with respect to
     the three most recent  years  before the Date of the Change of Control (the
     "Highest  Annual Bonus") and (ii) the Annual  Incentive  Compensation  most
     recently  received by the  Executive  and (y) a fraction,  the numerator of
     which is the number of days in such year  through the Date of  Termination,
     and the  denominator of which is 365, and (c) any  compensation  previously
     deferred by the Executive  (together with any accrued  interest or earnings
     thereon)  and any  unused and  accrued  vacation  pay,  in each case to the
     extent not theretofore  paid and in full  satisfaction of the rights of the
     Executive thereto;
 
 
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          (B) pay to the  Executive  an amount  equal to the  product of two (2)
     times the sum of the  Executive's  (x) Annual  Base  Salary and (y) Highest
     Annual Bonus,  payable in a single lump sum in cash within ten (10) days of
     the Date of Termination (to the extent  permitted under Section 409A of the
     Internal  Revenue  Code of 1986 as amended or  otherwise 6 months after the
     Date of Termination);
 
          (C) pay to the  Executive an  additional  monthly  retirement  annuity
     calculated  utilizing  the  assumptions  below and the  formulas  under the
     Company's  qualified  defined  benefit  retirement  plans (the  "Retirement
     Plans")  and any  excess  or  supplemental  retirement  plans in which  the
     Executive   participates,   including,   without   limitation,   the   SERP
     (collectively,   the  "SERPs").  For  purposes  of  this  calculation,  the
     following  assumptions  are to be  utilized:  (i) the  Executive's  will be
     deemed  to have  worked  an  additional  two  years  with  Compensation  as
     described in (iv) below with such time added as additional  time for either
     (a) accrued credited service under the Employees Retirement Plan of KeySpan
     Energy or (b) credited  service  pursuant to the Retirement  Income Plan of
     KeySpan  Energy,  (ii)  Executive's age will be deemed to have increased by
     two years;  (iii)  Executive is deemed to be an active employee at the time
     of commencement of benefits;  i.e. such Executive will not be a Term Vested
     for pension benefit calculation purposes;  and (iv) Compensation to be used
     for the two year period is the aggregate of the  Executive's  Annual Salary
     and  Highest  Annual  Bonus for each of the two years.  This  annuity  will
     commence at the time the Executive  commences to receive benefits under the
     Retirement Plan(s).
 
          (D)  continue to provide,  during the two year period  following  such
     termination of employment (the "Benefit  Period"),  the Executive with Life
     Insurance  Coverage  and the  benefits set forth in Clause (B) of paragraph
     (d)(iii)  of  Section  3, as if he had  remained  employed  by the  Company
     pursuant to this  Agreement  during the Benefit Period and then retired (at
     which time he will be treated as eligible for all retiree welfare  benefits
     and other benefits provided to retired senior  executives,  as set forth in
     Section  3(d)(iii));  provided,  however,  that  if the  Executive  becomes
     reemployed  with  another  employer  and is eligible to receive  medical or
     other welfare  benefits under another  employer-provided  plan, the medical
     and other  welfare  benefits  described  herein shall be secondary to those
     provided   under  such  other  plan  during  such   applicable   period  of
     eligibility; and
 
          To the extent any  benefits  described  in this Section 5(d) cannot be
     provided  pursuant to the  appropriate  plan or program  maintained  by the
     Company,  the Company  shall  provide  such  benefits  outside such plan or
     program at no additional  cost (including  without  limitation tax cost) to
     the Executive.
 
 
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<PAGE>
 
 
     6.  NON-EXCLUSIVITY  OF RIGHTS.  Nothing in this Agreement shall prevent or
limit the Executive's  continuing or future  participation in any plan, program,
policy or practice  provided by the Company or any of its  affiliated  companies
for which the  Executive may qualify,  nor,  subject to paragraph (f) of Section
13, shall  anything in this Agreement  limit or otherwise  affect such rights as
the Executive  may have under any contract or agreement  with the Company or any
of its  affiliated  companies.  Vested  benefits  and  other  amounts  that  the
Executive is otherwise  entitled to receive under the Annual  Incentive Plan and
Long Term Incentive Compensation Plan, the SERP, the Life Insurance Coverage, or
any other plan,  policy,  practice or program of, or any  contract or  agreement
with,  the Company or any of its  affiliated  companies  on or after the Date of
Termination  shall be  payable in  accordance  with the terms of each such plan,
policy, practice,  program, contract or agreement, as the case may be, except as
explicitly  modified  by this  Agreement.  Notwithstanding  the  foregoing,  the
Executive  shall have no right to receive any severance  pay or other  severance
benefits  under any plan or policy of the Company or under the  KeySpan  Amended
and Restated Senior Executive Change of Control Severance Plan.
 
     7. FULL STATEMENT.  The Company's  obligation to make payments provided for
in, and otherwise to perform its obligations  under, this Agreement shall not be
affected by any set-off, counterclaim, recoupment, defense or other claim, right
or action that the Company may have against the Executive or others. In no event
shall the  Executive  be obligated  to seek other  employment  or take any other
action by way of mitigation of the amounts payable to the Executive under any of
the provisions of this  Agreement,  and except as  specifically  provided in the
last proviso of the first sentence of Section 5(a)(C), such amounts shall not be
reduced, regardless of whether the Executive obtains other employment.
 
     8.  CONFIDENTIAL  INFORMATION.  The  Executive  shall  hold in a  fiduciary
capacity for the benefit of the Company all secret or confidential  information,
knowledge or data relating to the Company or any of its affiliated companies and
their  respective  business that the Executive  obtains  during the  Executive's
employment  by the Company or any of its  affiliated  companies  and that is not
public  knowledge  (other than as a result of the Executive's  violation of this
Section 8)  ("Confidential  Information").  The Executive shall not communicate,
divulge or disseminate  Confidential Information at any time during or after the
Executive's employment with the Company,  except in the course of performing his
duties  hereunder  or with  the  prior  written  consent  of the  Company  or as
otherwise  required  by law or legal  process.  In no event  shall any  asserted
violation of the  provisions  of this Section 8 constitute a basis for deferring
or  withholding  any  amounts  otherwise  payable  to the  Executive  under this
Agreement.
 
9.   CERTAIN ADDITIONAL PAYMENTS BY THE COMPANY.
 
     (a)  Anything in this  Agreement to the  contrary  notwithstanding,  in the
event it shall be determined  that any payment or distribution by the Company or
any of its affiliates,  or any one or more trusts established by the Company for
the benefit of its employees  to, or for the benefit of, the Executive  (whether
paid or payable or  distributed or  distributable  pursuant to the terms of this
Agreement or otherwise, but determined without regard to any additional payments
 
 
                                       10
<PAGE>
 
 
required under this Section 9) (a "Payment")  would be subject to the excise tax
imposed by Section 4999 of the Internal  Revenue Code of 1986 (the  "Code"),  as
amended or any interest or penalties are incurred by the Executive  with respect
to such  excise  tax (such  excise  tax,  together  with any such  interest  and
penalties,  are hereinafter  collectively referred to as the "Excise Tax"), then
the Executive  shall be entitled to receive an  additional  payment (a "Gross-Up
Payment")  in an amount such that after  payment by the  Executive  of all taxes
(including  any  interest or  penalties  imposed  with  respect to such  taxes),
including,  without limitation, any income taxes (and any interest and penalties
imposed with respect thereto) and Excise Tax imposed upon the Gross-Up  Payment,
the Executive  retains an amount of the Gross-Up Payment equal to the Excise Tax
imposed upon the Payments.
 
     (b)  Subject to the  provisions  of  paragraph  (c) of this  Section 9, all
determinations  required to be made under this Section 9, including  whether and
when a Gross-Up  Payment is required and the amount of such Gross-Up Payment and
the assumptions to be utilized in arriving at such determination,  shall be made
by  a  certified  public  accounting  firm  designated  by  the  Executive  (the
"Accounting Firm"), which shall provide detailed supporting calculations both to
the Company and the  Executive  within 15 business days of the receipt of notice
from the  Executive  that there has been a Payment,  or such  earlier time as is
requested by the Company.  In the event that the  Accounting  Firm is serving as
accountant or auditor for the  individual,  entity or group effecting the change
of control, the Executive shall appoint another nationally recognized accounting
firm to make the determinations  required hereunder (which accounting firm shall
then be referred to as the Accounting Firm hereunder).  All fees and expenses of
the Accounting Firm shall be borne solely by the Company.  Any Gross-Up Payment,
as  determined  pursuant to this  Section 9, shall be paid by the Company to the
Executive  within  five  (5)  days  of  the  receipt  of the  Accounting  Firm's
determination.  Any  determination  by the Accounting Firm shall be binding upon
the Company and the Executive. As a result of the uncertainty in the application
of  Section  4999 of the Code at the time of the  initial  determination  by the
Accounting Firm hereunder,  it is possible that Gross-Up Payments which will not
have been made by the Company should have been made ("Underpayment"), consistent
with the  calculations  required  to be made  hereunder.  In the event  that the
company  exhausts its remedies  pursuant to paragraph  (c) of this Section 9 and
the  Executive  thereafter  is required to make a payment of any Excise Tax, the
Accounting Firm shall determine the amount of the Underpayment that has occurred
and any such  Underpayment  shall be promptly  paid by the Company to or for the
benefit of the Executive.
 
     (c) The  Executive  shall notify the Company in writing of any claim by the
Internal  Revenue Service that, if successful,  would require the payment by the
Company of the Gross-Up  Payment.  Such  notification  shall be given as soon as
practicable  but not later than ten (10)  business  days after the  Executive is
informed in writing of such claim and shall apprise the Company of the nature of
such  claim  and the  date on which  such  claim is  requested  to be paid.  The
Executive  Shall not pay such claim prior to the  expiration  of the thirty (30)
day period  following  the date on which it gives such notice to the Company (or
such shorter period ending on the date that any payment of taxes with respect to
such claim is due).  If the Company  notifies the  Executive in writing prior to
the  expiration  of such  period  that it  desires to contest  such  claim,  the
Executive shall:
 
 
                                       11
<PAGE>
 
 
     (i)  give the Company any information  reasonably  requested by the Company
          relating to such claim,
 
     (ii) take such  action in  connection  with  contesting  such  claim as the
          Company  shall  reasonable  request  in  writing  from  time to  time,
          including,  without  limitation,  accepting legal  representation with
          respect  to such  claim  by an  attorney  reasonably  selected  by the
          Company,
 
     (iii)cooperate  with the  Company  in good  faith  in order to  effectively
          contest such claim; and
 
     (iv) permit the Company to participate in any proceedings  relating to such
          claim; PROVIDED, however, that the Company shall bear and pay directly
          all costs and expenses  (including  additional interest and penalties)
          incurred in connection  with such contest and shall indemnify and hold
          the Executive  harmless,  on an after-tax basis, for any Excise Tax or
          income tax  (including  interest and penalties  with respect  thereto)
          imposed as a result of such  representation  and  payment of costs and
          expenses.  Without  limitation  on the  foregoing  provisions  of this
          paragraph (c) of Section 9, the Company shall control all  proceedings
          taken in  connection  with such contest  and, at its sole option,  may
          pursue  or forego  any and all  administrative  appeals,  proceedings,
          hearings and conferences  with the taxing authority in respect of such
          claim and may, at its sole option,  either direct the Executive to pay
          the tax  claimed  and sue for a refund  or  contest  the  claim in any
          permissible manner, and the Executive agrees to prosecute such contest
          to a determination before any administrative  tribunal,  in a court of
          initial  jurisdiction  and in one or  more  appellate  courts,  as the
          Company  shall  determine;  PROVIDED,  however,  that  if the  Company
          directs  the  Executive  to pay such  claim and sue for a refund,  the
          Company  shall  indemnify  and  hold  the  Executive  harmless,  on an
          after-tax basis, from any Excise Tax or income tax (including interest
          or  penalties  with  respect  thereto)  imposed  with  respect to such
          advance or with  respect to any imputed  income  with  respect to such
          advance; and PROVIDED,  further,  that any extension of the statute of
          limitations  relating to payment of taxes for the taxable  year of the
          Executive with respect to which such contested amount is claimed to be
          due is  limited  solely to such  contested  amount.  Furthermore,  the
          Company's  control of the  contest  shall be  limited  to issues  with
          respect to which a Gross-Up Payment would be payable hereunder and the
          Executive shall be entitled to settle or contest,  as the case may be,
          any other issue  raised by the Internal  Revenue  Service or any other
          taxing authority.
 
     (d) If,  after the receipt by the  Executive  of an amount  advanced by the
Company  pursuant to  paragraph  (c) of this  Section 9, the  Executive  becomes
entitled to receive any refund with respect to such claim,  the Executive  shall
(subject to the Company's  complying with the  requirements  of paragraph (c) of
this Section 9) promptly pay to the Company the amount of such refund  (together
with any interest paid or credited thereon after taxes applicable thereto).  If,
after the receipt by the Executive of an amount advanced by the Company pursuant
to paragraph (c) of this Section 9, a  determination  is made that the Executive
shall not be entitled  to any refund with  respect to such claim and the Company
does not notify the Executive in writing of its intent to contest such denial of
refund prior to the  expiration of 30 days after such  determination,  then such
 
 
                                       12
<PAGE>
 
 
advance  shall be forgiven and shall not be required to be repaid and the amount
of such advance  shall  offset,  to the extent  thereof,  the amount of Gross-Up
Payment required to be paid.
 
     10.  INDEMNIFICATION.
 
     (a) The  Company  agrees  that if the  Executive  is  made a  party,  or is
threatened to be made a party, to any action suit or proceeding,  whether civil,
criminal,  administrative  or investigative (a  "Proceeding"),  by reason of the
fact that he is or was a  director,  officer or employee of the Company or is or
was  serving at the  request  of the  Company as a  director,  officer,  member,
employee or agent of another corporation,  partnership,  joint venture, trust or
other  enterprise,  including  service with respect to employee  benefit  plans,
whether or not the basis of such Proceeding is the Executive's alleged action in
an official capacity while serving as a director,  officer,  member, employee or
agent,  the Executive  shall be indemnified  and held harmless by the Company to
the fullest extent legally permitted or authorized by the Company's  certificate
of  incorporation  or bylaws or resolutions of the Company's  Board of Directors
or, if greater,  by the laws of the State of New York against all cost, expense,
liability and loss (including,  without limitation,  attorney's fees, judgments,
fines,  ERISA  excise  taxes  or  penalties  and  amounts  paid or to be paid in
settlement)  reasonably  incurred  or suffered by the  Executive  in  connection
therewith,  and such indemnification  shall continue as to the Executive even if
he has ceased to be a  director,  member,  employee  or agent of the  Company or
other entity and shall inure to the benefit of the Executive's heirs,  executors
and  administrators.  The Company shall advance to the Executive all  reasonable
costs and expenses  incurred by him in  connection  with a Proceeding  within 20
days after receipt by the Company of a written  request for such  advance.  Such
request  shall  include an  undertaking  by the Executive to repay the amount of
such advance if it shall  ultimately be determined that he is not entitled to be
indemnified against such costs and expenses.
 
     (b) Neither the failure of the Company  (including  its board of directors,
independent legal counsel or stockholders) to have made a determination prior to
the commencement of any proceeding  concerning payment of amounts claimed by the
Executive  under  Section 10(a) above that  indemnification  of the Executive is
proper  because  he  has  met  the  applicable   standard  of  conduct,   nor  a
determination  by the Company  (including  its board of  directors,  independent
legal counsel or  stockholders)  that the Executive has not met such  applicable
standard of conduct,  shall create a presumption  that the Executive has not met
the applicable standard of conduct.
 
     (c) The Company also agrees that if the  Executive  is made a party,  or is
threatened  to be made a party,  to any action,  suit or proceeding by reason of
the  termination  of his  employment  with his prior  employer or his  accepting
employment  with the Company,  he shall be indemnified  and held harmless by the
Company  against  all cost,  expense,  liability  and loss  (including,  without
limitation, attorney's fees) reasonably incurred or suffered by the Executive in
connection therewith.
 
 
                                       13
<PAGE>
 
 
     (d) The Company  agrees to continue and maintain a directors' and officers'
liability  insurance  policy  covering  the  Executive to the extent the Company
provides such coverage for its other executive officers.
 
11.  ATTORNEYS' FEES.
 
     The Company agrees to pay, as incurred,  to the fullest extent permitted by
law, all legal fees and expenses that the Executive  may  reasonably  incur as a
result of any contest (regardless of the outcome) by the Company,  the Executive
or others of the validity or  enforceability of or liability under, or otherwise
involving,  any  provision  of this  Agreement,  together  with  interest on any
delayed  payment  at  the  applicable  federal  rate  provided  for  in  Section
7872(f)(2)(A) of the Code.
 
12.  SUCCESSORS.
 
     (a) This  Agreement  is personal to the  Executive  and,  without the prior
written  consent  of the  Company,  shall  not be  assignable  by the  Executive
otherwise than by will or the laws of descent and  distribution.  This Agreement
shall  inure to the  benefit  of and be  enforceable  by the  Executive's  legal
representatives.
 
     (b) This  Agreement  shall inure to the benefit of and be binding  upon the
Company its  successors  and assigns,  provided  that the Company may not assign
this Agreement except in connection with the assignment or disposition of all or
substantially  all of the assets or stock of the Company,  or by law as a result
of a merger or consolidation.  In the event of such assignment, a failure by the
successor  to  specifically  assume in  writing,  delivered  to  Executive,  the
obligations and liabilities of the Company  hereunder shall be deemed a material
breach of this Agreement.
 
     (c) The Company shall require any successor (whether direct or indirect, by
purchase, merger, consideration or otherwise) to all or substantially all of the
business  and/or assets of the Company  expressly to assume and agree to perform
this  Agreement in the same manner and to the same extent that the Company would
have been  required to perform it if no succession  had taken place.  As used in
this  Agreement,  "Company" shall mean both the Company as defined above and any
such successor that assumes and agrees to perform this  Agreement,  by operation
of law or otherwise.
 
13.  MISCELLANEOUS.
 
     (a) This Agreement shall be governed by, and construed in accordance  with,
the laws of the State of New York,  without  reference to principles of conflict
of laws. The captions of this  Agreement are not part of the  provisions  hereof
and shall have no force or effect. This Agreement may not be amended or modified
except by a written agreement executed by the parties hereto or their respective
successors and legal representatives.
 
 
                                       14
<PAGE>
 
 
     (b) All notices and other  communications  under this Agreement shall be in
writing and shall be given by hand  delivery to the other party or by registered
or certified  mail,  return receipt  requested,  postage  prepaid,  addressed as
follows:
 
                  If to the Executive:   Mr. Robert B. Catell
                                         62 Osborne Road
                                         Garden City, N.Y.  11530
 
 
                  If to the Company:    KeySpan Corporation
                                        One Metrotech Center
                                        Brooklyn, N.Y, 11201
                           Attention:   General Counsel
 
     or to such other address as either party  furnishes to the other in writing
in accordance with this paragraph (b) of Section 13. Notices and  communications
shall be effective when actually received by the addressee.
 
     (c) The invalidity or  unenforceability  of any provision of this Agreement
shall not affect the validity or  enforceability  of any other provision of this
Agreement.  If any  provision  of  this  Agreement  shall  be  held  invalid  or
unenforceable  in part, the remaining  portion of such provision,  together with
all other  provisions of this Agreement,  shall remain valid and enforceable and
continue in full force and effect to the fullest extent consistent with law.
 
     (d)  Notwithstanding  any  provision  of this  Agreement,  the  Company may
withhold from amounts payable under this Agreement all federal, state, local and
foreign  taxes  that  are  required  to  be  withheld  by  applicable   laws  or
regulations.
 
     (e)  The  Executive's  or the  Company's  failure  to  insist  upon  strict
compliance  with any provision of, or to assert any right under,  this Agreement
(including,  without  limitation,  the  right  of  the  Executive  to  terminate
employment  for Good  Reason  pursuant  to  paragraph  (c) of  Section 4 of this
Agreement  shall not be deemed to be a waiver of such  provision  or right or of
any other provision of or right under this Agreement.
 
     (f)  The  Executive  and  the  Company   acknowledge  that  this  Agreement
supersedes any other agreement between them concerning the subject matter hereof
including  the  Employment   Agreement  between  the  Executive  and  MarketSpan
Corporation  and as  successor,  the  Company,  dated  September  10,  1998 with
amendments.
 
 
                                       15
<PAGE>
 
 
 
 
     (g) The rights and benefits of the Executive  under this  Agreement may not
be anticipated, assigned, alienated or subject to attachment, garnishment, levy,
execution  or other legal or  equitable  process  except as required by law. Any
attempt by the  Executive  to  anticipate,  alienate,  assign,  sell,  transfer,
pledge,  encumber or charge the same shall be void. Payments hereunder shall not
be considered assets of the Executive in the event of insolvency or bankruptcy
 
     (h) This Agreement may be executed in several  counterparts,  each of which
shall be deemed an original,  and said counterparts shall constitute but one and
the same instrument.
 
     IN WITNESS  WHEREOF,  the Executive has hereunto set the  Executive's  hand
and,  pursuant to the  authorization of its Board of Directors,  the Company has
caused this  Agreement  to be executed in its name and on its behalf,  all as of
the day and year first above written.
 
 
 
 
 
                                                 /s/Robert B. Catell
                                                 ----------------------------
                                                 Robert B. Catell
 
 
 
                                                 KEYSPAN CORPORATION
 
 
                                                 By: /s/Edward D. Miller
                                                     -------------------
                                                 Name:Edward D. Miller
                                                 Title:Director
 
 
 
 
 
 
 
 
 
 
                                       16
<PAGE>
 
 
 
 
                                   APPENDIX A
 
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN
 
 
 
     Pursuant to Section 3(d) of the Employment Agreement,  the parties agree as
follows:
 
         (a) Retirement Benefit.
             -------------------
 
     If the  Executive  terminates  employment  with  the  Company,  he shall be
eligible to receive a monthly pension,  commencing on the first day of the month
following such termination,  equal to the excess, if any, of (i) over the sum of
(ii), (iii), (iv) and (v) as follows:
 
 
          (i)  Sixty-five  percent (65%) of Final Average Pay on the Executive's
               date of  termination  of  employment;  if his years and months of
               service with the Company or its predecessors is less than 25, the
               65% shall be reduced in the proportion such service bears to 25.
 
          (ii) The amount payable  monthly from the KeySpan  Retirement  Plan or
               from any  successor  plan  thereto  in which the  Executive  is a
               member,  payable in the Normal Form of Benefit for this Plan,  as
               defined in subparagraph (c) herein;
 
          (iii)The  amount  payable   monthly  from  the  KeySpan   Supplemental
               Retirement  Plan or from any  successor  thereto,  payable in the
               Normal Form of Benefit for this Plan, as defined in  subparagraph
               (c) herein;
 
          (iv) The amount  payable  monthly from the KeySpan Excess Benefit Plan
               or from any  successor  thereto,  payable in the  Normal  Form of
               Benefit for this Plan, as defined in subparagraph (c) herein;
 
          (v)  One-half of the monthly amount of Primary Social Security benefit
               to which he would be entitled or is already  receiving  as of the
               date of termination.
 
     (b) For purposes of this Plan,  "Final  Average Pay" shall mean the monthly
average  of  base  salary  and  Annual  Incentive  Compensation  payable  to the
Executive over the 36 consecutive  calendar  months of employment for which such
average  is  highest.  In the event of a  reduction  to the  Executive's  annual
incentive  target  to a level  less  than  the  highest  level  approved  by the
Compensation and Management  Development Committee of the Board, the calculation
of annual  incentives  for pension  calculation  purposes  during the Employment
Period  shall be based  upon the  highest  incentive  target  level  during  the
 
 
                                       17
<PAGE>
 
 
Executive's  Employment  Period and not the reduced  incentive target level. For
this purpose,  no recognition shall be given to voluntary  deferrals,  Long-term
Incentive Compensation or any special short term incentives.  However,  pursuant
to the Boards  adoption of the Officer  Deferred Stock Unit Plan (DSU) effective
April 26, 2001, compensation deferred to the DSU plan shall be considered in the
calculation of Final Average Pay under this Plan.
 
     (c) The Normal Form of Benefit under this Plan is a 100% joint and survivor
annuity with the Executive's spouse at the time of termination of employment. If
he has no spouse at that time,  the normal  form  shall be a life  annuity.  The
Executive  may  elect to  receive  the  benefits  under  this  Plan in any other
actuarially  equivalent  form of  benefit,  including  a single lump sum. If the
Executive  elects a lump sum, it will be paid in cash within ten (10) days after
the Date of  Termination  (to the extent  permitted  under  Section  409A of the
Internal  Revenue  Code of 1986 as amended or  otherwise  no later than 6 months
after Date of  Termination).  For the benefit  accrued  during this  Agreement's
Employment  Period, an election with respect to the form of payment must be made
at least twelve months prior to the Executive's retirement.
 
     2. Pre-Retirement Death Benefit. In the event of the death of the Executive
prior to the commencement of benefits under this Plan, his surviving  spouse, if
any, shall be eligible to receive a monthly  pension for life  commencing on the
first of the month  following the  Executive's  death equal to the benefit which
would have been payable to the Executive if he had retired on the day before his
death and elected a 100% joint and survivor annuity with is spouse.
 
     3.  Disability  Benefits.  In the event the Executive  becomes  totally and
permanently  disabled as determined  by the Company,  he shall receive a monthly
benefit  under this Plan equal to that which  would have been  payable if he had
terminated employment of the date of disability.
 
     4. Actuarial  Determinations  Final.  The Company's  independent  actuarial
consultant's  determination  under  paragraphs  1, 2 and 3 shall  be  final  and
binding upon the Company and the Executive.
 
     5.  Forfeiture  of  Benefits.  If  the  Executive  voluntarily   terminates
employment with the Company for any reason other than death or disability  prior
to the completion of 10 years of service,  all benefits under this Plan shall be
forfeited.  For this purpose years of service shall include his employment  with
KeySpan Energy Corporation and Brooklyn Union Gas Company.
 
     6. Nature of Payments and  Obligations.  The Company shall  maintain one or
more  grantor  trusts or other  funding  vehicle as may be  satisfactory  to the
Executive,  which shall be  sufficient at any time to pay all benefits that have
accrued under the Plan.  Any payment due the  Executive or his surviving  spouse
shall be made from the assets of such trust or vehicle which,  for all purposes,
shall  continue  to be general  assets of the  Company.  To the extent  that the
Executive is entitled to payments from the Company  under this Plan,  such right
shall be that of an unsecured general creditor of the Company.
 
 
 
                                       18