Please direct your media and public relations inquiries to: mediarelations@cdw.com 800-800-4CDW CDW Corporation Files Registration Statement for Secondary Offering VERNON HILLS, Ill. - March 12, 2004 - CDW Corporation (Nasdaq: CDWC) announced that it has filed a registration statement with the Securities and Exchange Commission for the proposed public offering of up to 4,738,000 shares of the Company's common stock. The proposed offering consists of 4,120,000 shares to be sold by Michael P. Krasny, the Company's founder and former chief executive officer and current director and chairman emeritus, the Circle of Service Foundation and one or more additional entities affiliated with him. Mr. Krasny also intends to grant the underwriters an option to purchase from him up to 618,000 additional shares of common stock to cover over-allotments. All shares in the offering will be sold by the selling shareholders and the total number of shares outstanding will not change as a result of the offering. CDW will not sell any shares and will not receive any of the proceeds from the sales by the selling shareholders. After the offering, assuming the over-allotment option is not exercised, Mr. Krasny will beneficially own a total of approximately 18,321,901 million shares of the Company's common stock, or 21.8% of the total current outstanding common shares. At this level of ownership, Mr. Krasny will continue to be the Company's largest shareholder. The offering is being lead-managed by Morgan Stanley & Co. Incorporated. Co-managers of the offering include Goldman, Sachs & Co., William Blair & Company, L.L.C., Raymond James & Associates, Inc. and Robert W. Baird & Co. Incorporated. Copies of the prospectus may be obtained from Morgan Stanley & Co. Incorporated, 1585 Broadway, New York, NY 10036. A registration statement relating to these securities has been filed with the Securities and Exchange Commission but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time such registration statement becomes effective. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state. About CDW CDW® (Nasdaq: CDWC), ranked No. 381 on the FORTUNE 500, is a leading provider of technology products and services for business, government and education. CDW is a principal source of technology from top name brands such as APC, Apple, Cisco, HP, IBM, Microsoft, Sony, Symantec, Toshiba and ViewSonic. CDW distributes contracts to end users for customized and standardized on-site services supplied directly by providers such as HP Services and Unisys and for training programs provided by firms such as KnowledgeNet and Productivity Point International. CDW was founded in 1984 as a home-based business and today employs approximately 3,700 coworkers. In 2003, the company generated net sales of approximately $4.7 billion. CDW's direct model offers one-on-one relationships with knowledgeable account managers; purchasing by telephone, fax, the company's award-winning CDW.com Web site, customized CDW@work™ extranets, CDWG.com Web site and macwarehouse.com Web site; custom configured solutions and same day shipping; and pre- and post-sales technical support, with more than 100 factory-trained and A+ certified technicians on staff. Additional information can be found by visiting CDW.com.