CERTIFICATE OF INCORPORATION

                                       OF

                             CDW HOLDING CORPORATION

            FIRST: The name of the Corporation is CDW HOLDING CORPORATION;

            SECOND: The Corporation's registered office in the State of Delaware
is at Corporation Trust Center, 1209 Orange Street in the City of Wilmington,
County of New Castle. The name of its registered agent at such address is The
Corporation Trust Company.

            THIRD: The nature of the business of the Corporation and its purpose
is to engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of the State of Delaware.

            FOURTH: The total number of shares of all classes of stock which the
Corporation shall have authority to issue is 10,000,000 shares, consisting of
5,000,000 shares of Class A Common Stock, par value $.01 per share (herein
called "Class A Common Stock"), 5,000,000 shares of Class B Common Stock, par
value $.01 per share (herein called "Class B Common Stock").

            (a) Rights and Privileges of the Common Stock

            As used herein, the term "Common Stock" shall include the Class A
Common Stock and the Class B Common Stock. Except as otherwise provided herein,
all shares of Class A Common Stock and Class B Common Stock will be identical
and will entitle the holders thereof to the same rights and privileges.

            1. VOTING RIGHTS.

            Except as otherwise required by law or as otherwise provided herein,
on all matters submitted to the Corporation's stockholders, (i) the holders of
Class A Common Stock will be entitled to one vote per share and (ii) the holders
of Class B Common Stock will have no right to vote.


            2. DIVIDENDS.

            When and as dividends are declared thereon, whether payable in cash,
property or securities of the Corporation, the holders of Class A Common Stock
and the holders of Class B Common Stock will be entitled to share equally, share
for share, in such dividends, provided that if dividends are declared which are
payable in shares of Class A Common Stock or Class B Common Stock, dividends
will be declared which are payable at the same rate on each class of stock, and
the dividends payable in shares of Class A Common Stock will be payable to
holders of Class A Common Stock, and the dividends payable in shares of Class B
Common Stock will be payable to holders of Class B Common Stock.

            3. CONVERSION AND EXCHANGE.

            3A. Conversion of Class B Common Stock. Each record holder of Class
B Common Stock is entitled to convert any or all of the shares of such holder's
Class B Common Stock into the same number of shares of Class A Common Stock,
provided that no holder of Class B Common Stock is entitled to convert any share
or shares of Class B Common Stock to the extent that, as a result of such
conversion, such holder or its Affiliates would directly or indirectly own,
control or have power to vote a greater quantity of securities of any kind
issued by the Corporation than such holder and its Affiliates are permitted to
own, control or have power to vote under any law, regulation, order, rule or
other requirement of any governmental authority at any time applicable to such
holder and its Affiliates.

            3B. Exchange of Class A Common Stock. Each record holder of Class
A Common Stock is entitled to exchange any or all of the shares of such holder's
Class A Common Stock for the same number of shares of Class B Common Stock,
provided that no holder of Class A Common Stock is entitled to exchange any
share or shares of Class A Common Stock unless such holder or its Affiliates
would directly or indirectly own, control or have power to vote a greater
quantity of securities of any kind issued by the Corporation than such holder
and its Affiliates are permitted to own, control or have power to vote under any
law, regulation, order, rule or other requirement of any governmental authority
at any time applicable to such holder and its Affiliates if such shares were not
exchanged.


                                      2


            3C. Certain Conversion and Exchange Procedures. (i) Each
conversion of shares of Class B Common Stock into shares of Class A Common Stock
and each exchange of shares of Class A Common Stock for shares of Class B Common
Stock will be effected by the surrender of the certificate or certificates
representing the shares to be converted or exchanged, as the case may be, at the
principal office of the Corporation or the transfer agent designated by the
Corporation, if any, at any time during normal business hours, together with a
written notice by the holder of such shares stating either (A) the number of
shares of Class B Common Stock that such holder desires to convert into Class A
Common Stock and that upon such conversion such holder, together with its
Affiliates, will not directly or indirectly own, control or have the power to
vote a greater quantity of securities of any kind issued by the Corporation than
such holder and its Affiliates are permitted to own, control or have the power
to vote under any applicable law, regulation, order, rule or other governmental
requirement (and such statement will obligate the Corporation to issue such
Class A Common Stock), or (B) the number of shares of Class A Common Stock that
such holder desires to exchange for Class B Common Stock and that such exchange
is required in order for such holder and its Affiliates to comply with
applicable laws, regulations, orders, rules or other governmental requirements
as contemplated by paragraph 3B (and such statement will obligate the
Corporation to issue such Class B Common Stock). Such conversion or exchange
will be deemed to have been effected as of the close of business on the date on
which such certificate or certificates have been surrendered and such notice has
been received, and at such time the rights of any such holder with respect to
the converted Class B Common Stock or exchanged Class A Common Stock, as the
case may be, will cease and the person or persons in whose name or names the
certificate or certificates for shares of Class A Common Stock or Class B Common
Stock, as the case may be, are to be issued upon such conversion or exchange
will be deemed to have become the holder or holders of record of the shares of
Class A Common Stock or Class B Common Stock, as the case may be, represented
thereby.

            (ii) Promptly after such surrender and the receipt of the written
notice referred to in subparagraph (i) above, the Corporation will issue and
deliver in accordance with the surrendering holder's instructions the
certificate or certificates for the Class A Common Stock or Class B Common
Stock, as the case may be, issuable upon such conversion or


                                      3


exchange and a certificate representing any Class A Common Stock or Class B
Common Stock, as the case may be, which was represented by the certificate or
certificates delivered to the Corporation in connection with such conversion or
exchange but which was not converted or exchanged. The Corporation shall be
entitled to rely upon any written notice delivered pursuant to subparagraph (i)
above and such notice shall, in the absence of fraud, be binding and conclusive
upon the Corporation.

            4. MISCELLANEOUS PROVISIONS APPLICABLE TO COMMON STOCK.

            4A. Transfers. The Corporation will not close its books against
the transfer of Class B Common Stock or Class A Common Stock in any manner that
would interfere with the timely conversion of Class B Common Stock or exchange
of Class A Common Stock.

            4B. Subdivisions and Combinations of Shares. If the Corporation in
any manner subdivides or combines the outstanding shares of one class of Common
Stock, the outstanding shares of the other class of Common Stock will be
proportionately subdivided or combined.

            4C. Issuance Costs. The issuance of certificates for Class A
Common Stock upon conversion of Class B Common Stock or for Class B Common Stock
upon exchange for Class A Common Stock will be made without charge to the holder
or holders of such shares for any issuance tax (except stock transfer taxes) in
respect thereof or other cost incurred by the Corporation in connection with
such conversion or exchange and the related issuance of Class A Common Stock or
Class B Common Stock, as the case may be.

            5. DEFINITIONS.

            "Affiliate" shall mean, with respect to any Person, any other Person
directly or indirectly controlling, controlled by, or under common control with
such Person, provided that, for purposes of this definition, "control"
(including, with correlative meanings, the terms "controlled by" and "under
common control with"), as used with respect to any Person, shall mean the
possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of such Person, whether through the
ownership of voting securities or by contract or otherwise. Notwithstanding any
other provision herein, the


                                       4


Board of Directors shall in its good faith determine whether any party shall be
deemed an "Affiliate" of any Person for purposes of this Certificate of
Incorporation and such determination shall be binding and conclusive upon the
Corporation.

            "Person" shall mean and include an individual, a partnership, a 
joint venture, a corporation, a trust, an unincorporated organization and a 
government or any department or agency thereof.

            FIFTH: The name and mailing address of the incorporator is as 
follows:

            Euphemia B. Warren
            c/o Debevoise & Plimpton
            875 Third Avenue
            New York, New York 10022

            SIXTH: The following provisions are inserted for the management of
the business and for the conduct of the affairs of the Corporation and for the
purpose of creating, defining, limiting and regulating the powers of the
Corporation and its directors and stockholders:

            (a) The number of directors of the Corporation shall be fixed and
      may be altered from time to time in the manner provided in the By-Laws,
      and vacancies in the Board of Directors and newly created directorships
      resulting from any increase in the authorized number of directors may be
      filled, and directors may be removed, as provided in the By-Laws.

            (b) The election of directors may be conducted in any manner
      approved by the stockholders at the time when the election is held and
      need not be by ballot.

            (c) All corporate powers and authority of the Corporation (except as
      at the time otherwise provided by law, by this Certificate of
      Incorporation or by the By-Laws) shall be vested in and exercised by the
      Board of Directors.

            (d) No director of the Corporation shall be liable to the
      Corporation or its stockholders for monetary damages for breach of his or
      her fiduciary duty as a director, provided that nothing contained in


                                       5


      this Certificate of Incorporation shall eliminate or limit the liability
      of a director (i) for any breach of the director's duty of loyalty to the
      Corporation or its stockholders, (ii) for acts or omissions not in good
      faith or which involve intentional misconduct or a knowing violation of
      the law, (iii) under Section 174 of the General Corporation Law of the
      State of Delaware or (iv) for any transaction from which the director
      derived an improper personal benefit.

            (e) The Board of Directors shall have the power without the assent
      or vote of the stockholders to adopt, amend, alter or repeal the By-Laws
      of the Corporation, except to the extent that the By-Laws or this
      Certificate of Incorporation otherwise provide.

            SEVENTH: The Corporation reserves the right to amend or repeal any
provision contained in this Certificate of Incorporation in the manner now or
hereafter prescribed by the law of the State of Delaware, and all rights herein
conferred upon stockholders or directors are granted subject to this
reservation.

            IN WITNESS WHEREOF, I, the undersigned, being the incorporator
hereinabove named, for the purpose of forming a corporation pursuant to the
General Corporation Law of the State of Delaware, do make and file this
Certificate of Incorporation, hereby declaring and certifying that the facts
herein stated are true, and accordingly have hereunto set my hand this 17th day
of September, 1993.


                                                  /s/ Euphemia B. Warren
                                                  ------------------------------
                                                      Euphemia B. Warren


                                       6


STATE OF NEW YORK  )
                   : ss.:
COUNTY OF NEW YORK )

            BE IT REMEMBERED that on the 17th day of September, 1993,
personally appeared before me, Peter Demos , a notary public for the State of
New York, Eupheinia B. Warren, the party to the foregoing Certificate of
Incorporation, known to me personally to be such, and acknowledged said
Certificate of Incorporation to be their act and deed and that the facts therein
stated are true.

            GIVEN under my hand and seal of office the day and year aforesaid.



                                    /s/ Peter Demos
                                    --------------------------------------------
                                    Notary Public


                                   PETER DEMOS
                        Notary Public. State of New York                  [SEAL]
                                   No. 4985115
                           Qualified In Orange County
                       My Commission Expires June 24, 1995


                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                             CDW HOLDING CORPORATION

                     Pursuant to Section 242 of the General
                    Corporation Law of the State of Delaware

      CDW Holding Corporation (the "Corporation"), a corporation organized under
the General Corporation Law of the State of Delaware (the "General Corporation
Law") hereby certifies as follows:

      FIRST: That the Board of Directors of the Corporation, by written consent
in lieu of a meeting of its members in accordance with Section 141 (f) of the
General Corporation Law, duly adopted a resolution setting forth the following
proposed amendment to the Certificate of Incorporation of the Corporation and
declaring such amendment to be advisable:

            1. Article FIRST of the Certificate of Incorporation of the
      Corporation is hereby amended and restated in its entirety to read as
      follows:

                  "First: The name of the Corporation is WESCO International,
            Inc."


            SECOND: That in lieu of a meeting and vote of the stockholders of
the Corporation, the stockholders have by written consent, dated May 28, 1998,
approved the adoption of the foregoing amendment in accordance with the
provision of Section 228 of the General Corporation Law, and that such consent
has been filed with the minutes of the proceedings of the stockholders of the
Corporation.

            THIRD: That the foregoing amendment of the Certificate of
Incorporation was duly adopted pursuant to the applicable provisions of Sections
141, 228 and 242 of the General Corporation Law.

            IN WITNESS WHEREOF, the undersigned, being the duly authorized
President of the Corporation, for the purpose of amending the Certificate of
Incorporation of the Corporation pursuant to Section 242 of the General
Corporation Law of the State of Delaware, does make and file this Certificate,
hereby declaring and certifying that the facts herein stated are true, and
accordingly has hereunto set his hand, this 28th day of May, 1998.


                                    /s/ Roy W. Haley
                                    --------------------------------------------
                                    Roy W. Haley
                                    President


                         Certificate of Amendment of the
             Certificate of Incorporation of CDW Holding Corporation

                            Under Section 242 of the
                        Delaware General Corporation Law

            CDW HOLDING CORPORATION, a corporation organized and existing under
the laws of the State of Delaware (the "Corporation"), hereby certifies that:

            1. The Certificate of Incorporation of the Corporation was filed
with the Secretary of State of Delaware on September 17, 1993.

            2. The Certificate of Incorporation of the Corporation is hereby
amended, as authorized by Section 242 of the General Corporation Law of the
State of Delaware, to reduce the total number of shares of all classes of stock
that the Corporation shall have authority to issue.

            3. To effect such amendment, Article FOURTH of the Certificate of
Incorporation of the Corporation is hereby amended to read as follows:

                  "FOURTH: The total number of shares of all classes of stock
            that the Corporation shall have authority to issue is 4,000,000
            shares, consisting of 2,000,000 shares of Class A Common Stock, par
            value $.0l per share (herein called "Class A Common Stock"), and
            2,000,000 shares of Class B Common Stock, par value $.0l per share
            (herein called "Class B Common Stock")."


            4. The foregoing amendment of the Certificate of Incorporation of
the Corporation has been duly adopted in accordance with Sections 228 and 242 of
the General Corporation Law of the State of Delaware, by vote of the majority of
the Board of Directors and by written consent of the majority stockholder of the
Corporation. Written notice of the authorization of the foregoing amendment by
the majority stockholder has been given to all stockholders of the Corporation,
as provided in Section 228 of the General Corporation Law of the State of
Delaware.

            IN WITNESS WHEREOF, the Corporation has caused this certificate to
be executed by Roy W. Haley, its President, and attested by Jeffrey B. Kramp,
its Corporate Secretary, this 11th day of August, 1995. 


                                             /s/ Roy W. Haley
                                             -----------------------------------
                                             Roy W. Haley, President

Attest:


/s/ Jeffrey B. Kramp
- - - - ---------------------------------------
Jeffrey B. Kramp, Corporate Secretary