THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

CDW Corporation (CDWC)

4/7/2006 Proxy Information

Michael Krasny is our founder and currently serves as a director and is Chairman Emeritus. Mr. Krasny served as Chairman of the Board and our Chief Executive Officer from our inception through May 2001 and January 2001, respectively, and served as President from our inception through December 1990.

4/1/2005 Proxy Information

From his May 23, 2001 resignation as Chairman until December 31, 2004, Mr. Krasny participated in our health-insurance program on the same basis as our coworkers, except that he paid both the employer and coworker portions of the premiums associated with his coverage. Mr. Krasny no longer participates in our health-insurance program. Mr. Krasny served as Chairman and Chief Executive Officer of CDW Corporation from its inception in 1984 through May 2001 and January 2001, respectively, and served as President from its inception through December 1990.

4/16/2004 Proxy Information

Michael Krasny is our founder and currently serves as a director and is Chairman Emeritus. Mr. Krasny served as Chairman of the Board and our Chief Executive Officer from our inception through May 2001 and January 2001, respectively, and served as President from our inception through December 1990.

We agreed to pay the costs associated with an executive assistant for Mr. Krasny during the two-year period following his May 23, 2001 resignation as Chairman. We have extended this agreement for one year, but Mr. Krasny has reimbursed us for the costs incurred for the third year. In 2003, we paid approximately $65,344 for Mr. Krasny’s executive assistant under this arrangement.

In addition, Mr. Krasny participates in our health-insurance program on the same basis as our coworkers, except that he pays both the employer and coworker portions of the premiums associated with his coverage. As of December 31, 2004 Mr. Krasny will no longer participate in our health-insurance program.

4/13/2003 Proxy Information

On February 5, 2001, the Company entered into a registration rights agreement with each of Mr. Zeman and Mr. Kass (the “Registration Rights Agreements”). The Registration Rights Agreements give each of Mr. Zeman and Mr. Kass the right to demand (a “Registration Demand”), one time in each of calendar year 2001, 2002 and 2003, that the Company register some or all of the shares of Common Stock held by him at such time or to be acquired by him pursuant to the exercise of options under the MPK Stock Option Plan. The Company has the option, when a Registration Demand is presented to it, to either (i) purchase, at a per share price equal to $0.015 less than the then-current trading price, the shares subject to such Registration Demand, (ii) register such shares on a “shelf” registration statement pursuant to Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”), or (iii) register such shares on a registration statement under the Securities Act and cooperate with Mr. Zeman or Mr. Kass, as applicable, in developing and conducting an organized marketing campaign and “road show” relating to such registration statement. The Registration Rights Agreements contain customary conditions and limitations, including those relating to blackouts resulting from material non-public information which the Company should not be forced to disclose prematurely and to giving priority to Company financings.

On January 25, 2002, the Company received a Registration Demand from Mr. Zeman for 2,000,000 shares of Common Stock. On March 11, 2002, the Company filed a “shelf” registration statement pursuant to Rule 415 under the Securities Act covering the 2,000,000 shares of Common Stock. On March 26, 2002, Mr. Zeman exercised options under the MPK Stock Option Plan and sold the shares in an underwritten offering. Mr. Zeman received proceeds of $47.70 per share, which is net of the underwriting discount. The Company incurred $41,000 in expenses relating to the registration statement and the Company executed an underwriting agreement pursuant to which it agreed to certain indemnities, including under the securities laws.

On May 7, 2002, the Company purchased 384,376 shares of Common Stock from Mr. Kass at a total cost of $19.0 million ($49.50 per share). The closing price of a share of our Common Stock on The Nasdaq Stock Market on May 7, 2002 was $50.83. In connection with this purchase, Mr. Kass agreed to waive his right, as described above, to present a Registration Demand during 2002.

The Company agreed to pay the costs associated with an executive assistant for Mr. Krasny during the two-year period following his resignation effective May 23, 2001. The Company has extended this agreement for one year, but Mr. Krasny has agreed to reimburse the Company for the costs incurred by the Company for the third year. In 2002, the Company paid approximately $67,250 under this arrangement.