SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K (Mark One) X ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [NO FEE REQUIRED] for the fiscal year ended December 29, 2001 or _ TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [NO FEE REQUIRED] for the transition period from __________ to __________ COMMISSION FILE NUMBER 1-14989 A. Full title of the plan and address of the plan, if different from that of the issuer named below: WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive offices: WESCO INTERNATIONAL, Inc. Commerce Court, Suite 700 Four Station Square Pittsburgh, Pennsylvania 15219

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN INDEX TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - ------------------------------------------------------------------------------- PAGE Report of Independent Accountants 1 Financial Statements: Statements of Net Assets Available for Benefits December 29, 2001 and 2000 2 Statement of Changes in Net Assets Available for Benefits Year Ended December 29, 2001 3 Notes to Financial Statements 4-8 Supplemental Schedule: Schedule of Assets Held for Investment Purposes at End of Year December 29, 2001 9-11 Exhibits 12 Signature 12

REPORT OF INDEPENDENT ACCOUNTANTS To the Investment and Administrative Committees of WESCO Distribution, Inc. Retirement Savings Plan In our opinion, the accompanying statements of net assets available for benefits and the related statement of changes in net assets available for benefits present fairly, in all material respects, the net assets available for benefits of the WESCO Distribution, Inc. Retirement Savings Plan (the Plan) at December 29, 2001 and 2000, and the changes in net assets available for benefits for the year ended December 29, 2001 in conformity with accounting principles generally accepted in the United States of America. These financial statements are the responsibility of the Plan's management; our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these statements in accordance with auditing standards generally accepted in the United States of America, which require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion. Our audits were conducted for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedule of assets held for investment purposes is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. This supplemental schedule is the responsibility of the Plan's management. The supplemental schedule has been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole. /s/ PricewaterhouseCoopers LLP Pittsburgh, Pennsylvania June 7, 2002

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS DECEMBER 29, 2001 AND 2000 - ------------------------------------------------------------------------------- 2001 2000 Investments (Notes 2 and 6) $217,692,266 $228,644,477 Receivables: Employee contributions 474,098 899,567 Employer matching contributions 173,606 327,281 Accrued interest 21,067 50,556 ------------ ------------ Net assets available for benefits $218,361,037 $229,921,881 ============ ============ The accompanying notes are an integral part of these financial statements. - 2 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS YEAR ENDED DECEMBER 29, 2001 - ------------------------------------------------------------------------------- Additions: Employee contributions $ 12,737,351 Employee rollovers 1,230,900 Employer contributions 2,520,366 ------------ 16,488,617 Interest and dividend income 540,713 ------------ Total additions 17,029,330 ------------ Deductions: Distributions to withdrawing participants, at fair value 16,277,616 Net depreciation from registered investment companies 9,691,109 Net depreciation from common/collective trust funds 907,653 Net depreciation from stock funds and self-directed accounts 1,713,796 ------------ Total deductions 28,590,174 ------------ Net decrease 11,560,844 Net assets available for benefits, beginning of year 229,921,881 ============ Net assets available for benefits, end of year $218,361,037 ============ The accompanying notes are an integral part of these financial statements. - 3 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - -------------------------------------------------------------------------------- 1. MAJOR FEATURES OF THE PLAN WESCO Distribution, Inc. Retirement Savings Plan (the Plan) was established as of February 28, 1994 (date of inception). At the date of inception, certain employees of the predecessor company became employees of WESCO Distribution, Inc. (the Company) and participants in the Plan. At the date of inception, all funds held by the prior plans related to the transferred employees were transferred to the Plan. The Plan covers the current employees of the Company and those former employees with a fund balance of at least $5,000 who elected to maintain their funds in the Plan. Former employees cannot make contributions to the Plan. The Plan is subject to the Employee Retirement Income Security Act of 1974 (ERISA). Under the Plan, participants may elect to make contributions on a tax deferred basis in the form of a payroll deduction (Tax Deferred Contributions) ranging from 1% up to the lesser of 15% of their compensation or $10,500. In addition, employees may elect to make contributions on an after-tax basis in the form of a payroll deduction (After-Tax Contributions) ranging from 1% up to the lesser of 15% of their compensation or $10,500. The $10,500 may be adjusted in future years by the Internal Revenue Service. The sum of the Tax Deferred Contributions and the After-Tax Contributions cannot exceed 15% of the participant's compensation. Subject to limitation, the Company will make contributions (Regular Company Contributions) in an amount equal to 50% of a participant's total monthly contributions up to a maximum of 6%. In addition, the Company may, at the Board of Directors' discretion, make a profit sharing contribution (Company Profit Sharing Contribution) to the Plan provided certain predetermined profit levels are attained. The Company did not make a Profit Sharing Contribution for the year ended December 29, 2001. Participants are fully vested in the value of their contributions and related investment income at all times and vest in their allocated share of employer contributions according to the following schedule: Less than three years of service 0% Three years of service 33% Four years of service 66% Five or more years of service 100% In conjunction with a leveraged recapitalization of the Company all active employees as of June 5, 1998 became fully vested. Employer contributions forfeited by participants not vested at their termination date are used to reinstate previously forfeited account balances of former participants who have returned to employment with the Company, or to reduce employer contributions in accordance with the plan document. Total forfeitures that reduced employer contributions in 2001 were approximately $2,022,000. - 4 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - -------------------------------------------------------------------------------- Ten options were available for investment of contributions to the Plan as of December 29, 2001. A brief description of the investment options is as follows: FUND DESCRIPTION American Express Trust Income Fixed income fund that invests Fund II exclusively in American Express Trust Income Fund I, which invests in a diversified pool of insurance and bank investment contracts and book value investment contracts of varying maturity size and yield to preserve principal and income American Express Trust Equity Index Diversified corporate stock fund that Fund I seeks to achieve a return as close as possible to the Standard and Poor's 500 Stock Index AXP Selective Fund Investment grade bond fund that seeks current income and preservation of capital American Balanced Fund Broadly diversified fund that invests in securities and bonds for the preservation of capital, current income and long-term growth of capital and income AXP New Dimension Fund Common stock fund that seeks companies showing potential for significant growth for long-term growth of capital PIMCO Opportunity Fund Common stock fund that seeks companies with small equity capitalization to achieve capital appreciation Templeton Foreign Fund Aggressive long-term capital growth fund that invests in common stocks of companies outside the United States American Century Value Fund Long-term capital growth fund that invests in securities that its management believes are undervalued at the time WESCO International Stock Fund Fund that invests in the stock of WESCO International, Inc. Self-Directed Brokerage Account Account that provides participants access to a wide range of common stocks and mutual funds beyond those available through the Plan. In addition, participant account balances transferred from the prior plans may remain invested in the Viacom (formerly CBS Corporation) Pooled Stock Fund, although no future contributions may be invested in the Viacom Pooled Stock Fund. Investment income earned by the Viacom Pooled Stock Fund is invested in the American Express Trust Income Fund II in accordance with the plan document. As a result of the initial public offering of WESCO International, Inc., participants were also given the option to invest in the WESCO International Stock Fund effective July 1, 1999. An account is maintained for each participant, which is credited with the participant's contributions and an allocation of Company contributions and plan earnings. Allocations are based on participant contributions or account balances, as defined by the Plan. The benefit to which a participant is entitled is the benefit that can be provided from that participant's account. - 5 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - -------------------------------------------------------------------------------- The Investment Committee and the Administrative Committee of the Company's Board of Directors administer the Plan. Reference should be made to the Prospectus, "What Does Your Future Hold?", for additional information on the Plan. 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES ACCOUNTING PRINCIPLES The financial statements of the Plan have been prepared in accordance with accounting principles generally accepted in the United States of America. The following are the significant accounting policies followed by the Plan: BASIS OF ACCOUNTING The accounting records of the Plan are maintained on the accrual basis of accounting. INVESTMENT VALUATION AND INCOME RECOGNITION Investments are carried at fair value in the accompanying financial statements. Investments in registered investment companies, common/collective trust funds and common stocks are valued by the trustee based on market values of all assets in the funds' securities portfolio and the number of units in the funds owned by the Plan. Investments in the Viacom Pooled Stock Fund and WESCO International Stock Fund are valued at quoted market prices. Participant loans are valued at cost which approximates fair value. Purchases and sales of securities are recorded on a settlement date basis. Dividends are recorded on the ex-dividend date. NET APPRECIATION (DEPRECIATION) IN VALUE OF INVESTMENTS The Plan presents in the statement of changes in net assets available for benefits the net appreciation (depreciation) in the fair value of its investments, which consists of the realized gains (losses) and the unrealized appreciation (depreciation) in common/collective trusts, registered investment companies, Viacom and WESCO International stock and other common stocks. USE OF ESTIMATES The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make significant estimates and assumptions. These may affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of additions and deductions during the reporting period. Actual results could differ from those estimates. RISKS AND UNCERTAINTIES The Plan provides for various investment options in any combination of stocks, bonds, fixed income securities and other investment securities. Investment securities are exposed to various risks, such as interest rate, market and credit. Due to the level of risk associated with certain investment securities and the level of uncertainty related to changes in the value of investment securities, it is at least reasonably possible that changes in the near-term could materially affect participants' account balances and the amounts reported in the statements of net assets available for benefits and the statement of changes in net assets available for benefits. - 6 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - -------------------------------------------------------------------------------- OTHER Administrative expenses, excluding participant loan setup fees, distribution fees and hardship withdrawal fees, are paid by the Company and, therefore, are not expenses of the Plan. Benefits are recorded when paid. 3. TAX STATUS The Internal Revenue Service has ruled that the Plan qualifies under Section 401(a) of the Internal Revenue Code and, therefore, is exempt from federal income taxes under provisions of Section 501(a). Accordingly, no provision for income taxes has been included in the Plan's financial statements. 4. EMPLOYEE LOANS Participants are permitted to borrow against a portion of their vested account balance within the prescribed limitations and pursuant to nondiscriminatory rules established by the Administrative Committee. Each loan is to be repaid over a period not to exceed five years. The interest rate applied to employee loans is established each month by the Administrative Committee at 1% above the PNC Bank prime interest rate. The interest rate on new loans ranged between 6.0% and 10.5% for the period December 30, 2000 to December 29, 2001. Principal and interest payments are generally made through monthly payroll deductions and are credited to the participant's individual account. Loans of approximately $2,506,000 were made from the Plan and loan principal repayments of approximately $3,534,000 were received by the Plan for the year ended December 29, 2001. Interest of approximately $570,000 was received by the Plan for the year ended December 29, 2001 related to employee loans. 5. PLAN TERMINATION Although the Company has not expressed any intent to do so, it has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA. In the event the Plan terminates, participants will become 100% vested in their accounts. - 7 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN NOTES TO FINANCIAL STATEMENTS DECEMBER 29, 2001 AND 2000 - -------------------------------------------------------------------------------- 6. INVESTMENTS Investments representing 5% or more of the net assets available for benefits as of December 29, 2001 and 2000 were as follows: 2001 2000 American Express Trust Income Fund II $55,526,062 $52,261,139 American Express Trust Equity Index Fund I 30,435,480 36,682,066 American Balanced Fund 23,810,287 19,356,693 AXP New Dimension Fund 49,893,506 63,185,416 PIMCO Opportunity Fund 15,655,044 19,277,807 7. RELATED PARTY TRANSACTIONS Certain investments of the Plan are mutual funds managed by American Express. The trustee of the Plan is American Express Trust Company and, therefore, these transactions qualify as party-in-interest transactions. - 8 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN SCHEDULE OF ASSETS HELD FOR INVESTMENT PURPOSES AT END OF YEAR EIN 25-1723345, PLAN NUMBER 001 DECEMBER 29, 2001 - ------------------------------------------------------------------------------- FAIR ISSUER DESCRIPTION VALUE American Express Trust American Express Trust Income Company* Fund II $ 55,526,062 American Express Trust American Express Trust Equity Company* Index Fund I 30,435,480 American Express Financial* AXP Selective Fund 7,303,117 American Funds American Balanced Fund 23,810,287 American Express Financial* AXP New Dimension Fund 49,893,506 PIMCO Funds PIMCO Opportunity Fund 15,655,044 Templeton Group Templeton Foreign Fund 5,939,500 American Century Investments American Century Value Fund 9,012,758 Viacom Viacom Pooled Stock Fund 9,720,511 WESCO International, Inc.* WESCO International Stock Fund 3,795,391 Participant Loans* 6.0% - 10.5%, due at various dates 5,829,874 Global Crossing Ltd. Common Stock 2,889 Creative Technology Common Stock 740 AES Corp. Common Stock 4,378 AOL Time Warner Inc. Common Stock 3,350 Adobe Systems Inc. Common Stock 3,208 Advanced Micro Devices, Inc. Common Stock 16,530 Altera Corp. Common Stock 2,276 Amazon Com Inc. Common Stock 747 American Eagle Outfitters, Inc. Common Stock 11,731 Andrea Electronics Corp. Common Stock 690 Applied Materials, Inc. Common Stock 5,564 Aquila Inc. Common Stock - Ariba Inc. Common Stock 856 Art Technology Inc. Common Stock 320 Artemis Intl Solutions Corp. Common Stock 46 Big Dog Holdings Inc. Common Stock 301 Boeing Co. Common Stock 1,404 CTS Corp. Common Stock 1,500 Callaway Golf Co. Common Stock 798 Calpine Corp. Common Stock 7,330 Cisco Systems Inc. Common Stock 2,453 Comfort Systems USA, Inc. Common Stock 340 Comdisco Inc. Common Stock 740 Corning Inc. Common Stock 5,130 DCH Technology Inc. Common Stock 260 Dell Computer Corp. Common Stock 4,748 Walt Disney Co. Common Stock 3,071 - 9 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN SCHEDULE OF ASSETS HELD FOR INVESTMENT PURPOSES AT END OF YEAR EIN 25-1723345, PLAN NUMBER 001 DECEMBER 29, 2001 - ------------------------------------------------------------------------------- FAIR ISSUER DESCRIPTION VALUE Docent Inc. Common Stock $ 2,170 Enron Corp. Common Stock 260 Erickson LM Telephone Co. Common Stock 546 Ford Motor Co. Common Stock 1,894 Genetech Inc. Common Stock 3,447 General Motors Common Stock 1,740 Genetronics Biomedical Ltd. Common Stock 4,860 Home Depot Inc. Common Stock 6,998 ICN Pharmaceuticals, Inc. Common Stock 2,978 Immunex Corp. Common Stock 2,700 Intel Corp. Common Stock 9,798 Interliant Inc. Common Stock 43 JDS Uniphase Corp. Common Stock 20,160 Johnson & Johnson Common Stock 11,650 Kaire Holdings Inc. Common Stock 24 Krispy Kreme Doughnuts Inc. Common Stock 7,450 LTV Corp. Common Stock 82 LSI Logic Corp. Common Stock 2,844 LA Quinta Corp. Common Stock 59,267 MTR Gaming Group Inc. Common Stock 542 Medical Action Industries, Inc. Common Stock 5,250 Metal Clad Corp. Common Stock 235 Metro One Telecommunications, Inc. Common Stock 860 Motorola Inc. Common Stock 3,143 Nisource Inc. Common Stock 209 Nokia Corp. Common Stock 5,753 Nortel Networks Corp. Common Stock 304 Novatel Wireless, Inc. Common Stock 1,440 N2H2 Inc. Common Stock 41 Oracle Corp. Common Stock 37,404 Owens Corning Comm Common Stock 835 Paychex Inc. Common Stock 5,252 Photoworks, Inc. Common Stock 12 Polymedica Corp. Common Stock 9,200 PurchasePro.Com Inc. Common Stock 75 Quadramed Corporation Common Stock 1,079 - 10 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN SCHEDULE OF ASSETS HELD FOR INVESTMENT PURPOSES AT END OF YEAR EIN 25-1723345, PLAN NUMBER 001 DECEMBER 29, 2001 - ------------------------------------------------------------------------------- FAIR ISSUER DESCRIPTION VALUE RSA Sec Inc. Common Stock $ 1,575 Radio Shack Corporation Common Stock 2,896 Remington Oil & Gas Corp. Common Stock 3,258 Savvis Communications Corp. Common Stock 66 Starrett L S Company Common Stock 970 Sun Microsystems Inc. Common Stock 712 Taiwan Semiconductor Manufacturing Co. Common Stock 6,499 Take-2 Interactive Sft. Common Stock 1,394 Tellabs Inc. Common Stock 2,292 Telular Corp. Common Stock 2,820 Texas Instruments Inc. Common Stock 3,205 Triquint Semiconductor Inc. Common Stock 3,975 USG Corporation Common Stock 1,024 United Energy Corp. Common Stock 9,125 USAIR Group Common Stock 4,120 Uromed Corp. Common Stock 74 View Systems Inc. Common Stock - Wal-Mart Stores Inc. Common Stock 5,515 Artisan Partners Artisan International Investor Shares 8,524 Artisan Partners Artisan Mid Cap Fund (Investor Shares) 22,977 Fremont Funds Fremont Mutual Funds Inc. 26,229 Harbor Fund Harbor Capital Appreciation Fund 58,331 The Oakmark Family of Funds Oakmark Equity and Income Fund (1) 4,924 PIMCO Funds PIMCO FDS Multi Manager Ser. 5,117 Dresdner RCM Global Investors RCM Global Health D. 5,178 Potomac Funds Potomac Funds 51,541 The Reserve Funds Reserve Fund Inc. CL A 199,283 The Selected Fund Selected American Shares Inc. 31,957 Third Avenue Funds Third Ave Tr. 2,914 Thompson Plumb and Associates Thompson Plumb Funds Inc. 5,502 Weitz Funds Weitz Partners Value Fund 3,896 Weitz Funds Weitz Ser. Fund Inc. 2,898 ------------- Total $ 217,692,266 ============= *Denotes party-in-interest. - 11 -

WESCO DISTRIBUTION, INC. RETIREMENT SAVINGS PLAN SCHEDULE OF ASSETS HELD FOR INVESTMENT PURPOSES AT END OF YEAR EIN 25-1723345, PLAN NUMBER 001 DECEMBER 29, 2001 - ------------------------------------------------------------------------------- EXHIBITS The following exhibits are filed or incorporated as part of this report: Exhibit Number Description ------- ----------- 23.01 Consent of PricewaterhouseCoopers LLP (filed herewith) SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the Administrative Committee for the WESCO Distribution, Inc. Retirement Savings Plan has duly caused this annual report to be signed on its behalf by the undersigned thereunto duly authorized. WESCO DISTRIBUTION, INC. RESTIREMENT SAVINGS PLAN Date: June 25, 2002 By: /s/ Stephen A. Van Oss ---------------- --------------------------------- - 12 -

Exhibit 23.01 CONSENT OF INDEPENDENT ACCOUNTANTS ---------------------------------- We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-91187) of WESCO International, Inc. of our report dated June 7, 2002 relating to the financial statements of the WESCO Distribution, Inc. Retirement Savings Plan, which appears in this Form 11-K. /s/ PricewaterhouseCoopers LLP Pittsburgh, Pennsylvania June 25, 2002