UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

(Mark One)

Commission file number 0-21796

CDW Corporation

(847) 465-6000
(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes þ No o

Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act) Yes þ No o

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

As of May 4, 2005, 92,763,516 common shares were issued and 81,543,116 were outstanding.

CDW CORPORATION AND SUBSIDIARIES
INDEX

ii

Part I. Financial Information

CDW CORPORATION AND SUBSIDIARIES

The accompanying notes are an integral part of the consolidated financial statements.

1

CDW CORPORATION AND SUBSIDIARIES

The accompanying notes are an integral part of the consolidated financial statements.

2

CDW CORPORATION AND SUBSIDIARIES

The accompanying notes are an integral part of the consolidated financial statements.

3

CDW CORPORATION AND SUBSIDIARIES

(1)

The Company acquired $14.6 million and $6.7 million of shares for treasury purposes in March 2005 and 2004, respectively, for which cash settlement occurred in April 2005 and 2004, respectively. Accordingly, the Company has excluded these non-cash items from both the “Purchase of treasury shares” and “Accounts payable” amounts presented above.

The accompanying notes are an integral part of the consolidated financial statements.

4

CDW CORPORATION AND SUBSIDIARIES

1.	Description of Business
	CDW Corporation (collectively with its subsidiaries, “CDW” or the “Company”) is a leading direct marketer of multi-brand computers and related technology products and services in the United States. Our primary business is conducted from a combined corporate office and distribution center located in Vernon Hills, Illinois, and sales offices in Illinois, Virginia, Connecticut, New Jersey, and Toronto, Canada. Additionally, we market and sell products through CDW.com, CDWG.com, macwarehouse.com and CDW.ca, our Web sites.
2.	Summary of Significant Accounting Policies
	Basis of Presentation
	The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America. Such principles were applied on a basis consistent with those reflected in our Annual Report on Form 10-K for the year ended December 31, 2004 (“2004 Form 10-K”) and documents incorporated therein as filed with the Securities and Exchange Commission. The accompanying financial data should be read in conjunction with the notes to consolidated financial statements contained in the 2004 Form 10-K and documents incorporated therein. In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all adjustments necessary to present fairly our financial position as of March 31, 2005 and December 31, 2004, the results of operations for the three month periods ended March 31, 2005 and 2004, the cash flows for the three month periods ended March 31, 2005 and 2004, and the changes in shareholders’ equity for the three month period ended March 31, 2005. The unaudited condensed consolidated statements of income for such interim periods are not necessarily indicative of results for the full year.
	Use of Estimates
	The preparation of financial statements in accordance with accounting principles generally accepted in the United States of America requires management to make use of certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported periods. We base our estimates on historical experience and on various other assumptions that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. See the audited consolidated financial statements and notes thereto included in the 2004 Form 10-K for an additional discussion of the most significant accounting policies and estimates used in the preparation of our financial statements.
	Reclassifications
	Certain reclassifications have been made to the prior year financial statements to conform to the current year presentation.
	Stock-Based Compensation
	At March 31, 2005, we had several stock-based employee compensation plans. We have adopted the disclosure provision of Statement of Financial Accounting Standards No. 148, “Accounting for Stock-Based Compensation – Transition and Disclosure,” which amends Statement of Financial Accounting Standards

5

No. 123, “Accounting for Stock-Based Compensation” (“SFAS 123”). As allowed by SFAS 123, we account for our stock-based compensation programs according to the provisions of Accounting Principles Board Opinion No. 25, “Accounting for Stock Issued to Employees” (“APB 25”). Accordingly, compensation expense is recognized to the extent of employee or director services rendered based on the intrinsic value of compensatory options or shares granted under the plans. The following table illustrates the effect on net income and earnings per share if we had applied the fair value recognition provisions of SFAS 123 to stock-based employee compensation for the three month periods ended March 31, 2005 and 2004 (in thousands, except per share amounts):

3.	Recently Issued Accounting Standard
	In December 2004, the Financial Accounting Standards Board (“FASB”) issued Statement of Financial Accounting Standards No. 123R, “Share-Based Payment” (“SFAS 123R”), which requires the Company to measure all share-based payments to coworkers under our stock-based compensation plans using a fair-value-based method and record compensation expense related to these payments in our consolidated financial statements. In April 2005, the Securities and Exchange Commission adopted a new rule amending the effective date for SFAS 123R. Under the new rule, SFAS 123R is effective for the first annual period beginning after June 15, 2005; therefore, we are required to adopt SFAS 123R for the year beginning January 1, 2006. The pro forma disclosures previously required under SFAS 123 will no longer be an alternative to financial statement recognition. We intend to use the modified prospective application transition method upon adopting SFAS 123R, which allows for prospective recognition of compensation expense without restatement of prior periods in the year of adoption.
	As discussed in Note 2 above, we account for our stock-based compensation programs according to the provisions of APB 25. Accordingly, compensation expense is recognized to the extent of employee or director services rendered based on the intrinsic value of compensatory options or shares granted under the plans.
	Historically, stock options have been granted annually to all CDW coworkers as part of the Company’s overall compensation plan. After studying the potential impact of SFAS 123R, the Compensation and Stock Option Committee (the “Committee”) of the Company’s Board of Directors approved certain modifications to the Company’s current compensation structure. As modified, the Company’s compensation structure will

6

include the following features:

	•	CDW officers, directors and managers will participate in the Company’s employee stock option plan on an annual basis. Except as noted below, these grants will be determined in a manner consistent with how prior grants have been determined.
	•	Coworkers below manager level will no longer be granted options on an annual basis. There may be minor, discrete grants made to specific coworkers below manager level in recognition of outstanding performance or significant contribution to the Company.
	•	All coworkers will be eligible for an additional discretionary profit-sharing contribution from the Company to the CDW Corporation Employees’ Profit Sharing Plan (the “Plan”). The amount of the discretionary contribution, if any, will be determined annually by the Committee. The Committee has approved a $1,000 profit sharing contribution with respect to each coworker who is eligible to participate in the Plan and is employed on December 31, 2005. The cost of this 2005 contribution is estimated to be approximately $4 million (pre-tax). The actual cost will depend on the number of coworkers eligible to participate in the Plan and employed on December 31, 2005. In 2005, CDW officers, directors and managers have, as an offset to the increased contribution, received slightly fewer options than they otherwise would have received.
	•	All unvested options granted prior to January 1, 2005 held by coworkers at the manager level and below who are employed on December 31, 2005 will become fully vested effective December 31, 2005. As of April 29, 2005, coworkers at the manager level and below held unvested options to purchase approximately 3.3 million shares.

	The acceleration of vesting is being undertaken primarily so that compensation expense for the accelerated options will not be recognized in the Company’s income statement in future periods upon adoption of SFAS 123R. It is estimated that the compensation expense for stock options will be approximately $16 million (pre-tax) in 2006, reflecting revisions to the compensation structure, along with some changes to the valuation model permitted under SFAS 123R. This estimate is based on the assumption that an additional contribution would be made to the Plan for 2006 similar to the contribution to be made for 2005, an assumption regarding the number of stock options that would be forfeited and an assumption of the number of options that would be granted in the last three quarters of 2005 and in 2006 and the valuation of such stock options at the time of grant.
	In connection with the acceleration of vesting, the Company expects to take a charge in the fourth quarter of 2005. The amount of the charge will be tied in part to the intrinsic value of the accelerated options on the date of acceleration. It is not yet possible to determine the intrinsic value of those options on December 31, 2005. However, if the accelerated vesting were to occur as of April 29, 2005, the charge would be approximately $8 million (pre-tax), as determined in accordance with the provisions of APB 25.
	In addition, after studying the potential impact of SFAS 123R, certain modifications to the Company’s Employee Stock Purchase Plan (“ESPP”) were approved. The ESPP provides that eligible coworkers may contribute up to 15% of their eligible compensation towards the quarterly purchase of our common stock. Historically, the coworkers’ purchase price was 85% of the lesser of the fair market value of the stock on the first business day or the last business day of the quarterly offering period. Effective January 1, 2006, the coworkers’ purchase price will be 95% of the fair market value of the stock on the last business day of the quarterly offering period.
4.	Marketable Securities
	The amortized cost and estimated fair values of our investments in marketable securities at March 31, 2005 were (in thousands):

7