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                                                                     Exhibit 5.1

                               September 15, 2000



Cable Design Technologies Corporation
Foster Plaza 7
661 Andersen Drive
Pittsburgh, PA  15220

Ladies and Gentlemen:

         We are acting as special counsel to Cable Design Technologies
Corporation, a Delaware corporation (the "Corporation"), in connection with its
registration statement on Form S-3 (the "Registration Statement"), being filed
with the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Securities Act"), on the date hereof in connection with the
proposed offer and sale of the following securities (collectively, the
"Securities") of the Corporation having an aggregate initial offering price of
up to $150,000,000:

         (i)      senior debt securities (the "Senior Debt Securities");

         (ii)     subordinated debt securities (the "Subordinated Debt
                  Securities," and together with the Senior Debt Securities, the
                  "Debt Securities"); and

         (iii)    common stock, par value $.01 per share (the "Common Stock"),
                  of the Corporation.

         The Securities may be offered in separate series, in amounts, at
prices, and on terms to be set forth in the prospectus and one or more
supplements to the prospectus (collectively, the "Prospectus") constituting a
part of the Registration Statement, and in the Registration Statement.

         The Debt Securities are to be issued under one or more indentures
generally in the form incorporated by reference as Exhibit 4.3 to the
Registration Statement (the "Indentures").

         Certain terms of the Securities to be issued by the Corporation form
time to time will be approved by the Board of Directors of the Corporation or a
committee thereof or certain authorized officers of the Corporation as part of
the corporate action taken and to be taken (the "Corporate Proceedings") in
connection with issuance of the Securities. We have examined or are otherwise
familiar with the Amended and Restated Certificate of Incorporation of the
Corporation, the Bylaws of the Corporation, as amended, the Registration
Statement, such of the Corporate Proceedings as have occurred as of the date
hereof, and such other documents, records and instruments as we have deemed
necessary or appropriate for the purposes of this opinion letter.
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         For purposes of this opinion letter, we have assumed the authenticity
of all documents submitted to us as originals, the conformity to the originals
of all documents submitted to us as copies and the authenticity of the originals
of all documents submitted to us as copies. We have also assumed the legal
capacity of all natural persons, the genuineness of the signatures of persons
signing all documents in connection with which this opinion is rendered, the
authority of such persons signing on behalf of the parties thereto other than
the Corporation and the due authorization, execution and delivery of all
documents by the parties thereto other than the Corporation. As to any facts
material to the opinions expressed herein, we have relied upon the statements
and representations of officers and other representations of the Corporation and
others.

         Our advice on every legal issue addressed in this letter is based
exclusively on the internal laws of the State of New York, the General
Corporation Law of the State of Delaware and the federal law of the United
States of America, and represents our opinion as to how that issue would be
resolved were it to be considered by the highest court in the jurisdiction which
enacted such law. The manner in which any particular issue would be treated in
any actual court case would depend in part on facts and circumstances particular
to the case, and this opinion letter is not intended to guarantee the outcome of
any legal dispute which may arise in the future.

         Based upon and subject to the foregoing qualifications, assumptions and
limitations and the further limitations set forth below, we hereby advise you
that in our opinion:

(i) the Debt Securities, when authorized and sold as contemplated in the
Registration Statement, will be validly issued by the Corporation and will
constitute valid and legally binding obligations of the Corporation, enforceable
in accordance with their terms; and

(ii) the Common Stock, when authorized and sold as contemplated in the
Registration Statement, will be validly issued by the Corporation and will be
duly authorized, fully paid and non-assessable.

         The foregoing opinions assume that (i) the consideration designated in
the applicable Corporate Proceedings for any Common Stock shall have been
received by the Corporation in accordance with applicable law; (ii) the
applicable Indenture shall have been duly authorized, executed and delivered by
all parties thereto other than the Corporation; (iii) the Registration Statement
shall have become effective under the Securities Act; and (iv) the applicable
Indenture shall have become duly qualified under the Trust Indenture Act of
1939, as amended.

         Our opinion in paragraph (i) of this opinion letter is subject to: (A)
the effect of bankruptcy, insolvency, fraudulent conveyance and other similar
laws and judicially developed doctrines in this area such as substantive
consolidation and equitable subordination; (B) the effect of general principles
of equity; and (C) other commonly recognized statutory and judicial constraints
on enforceability including statutes of limitations. "General principles of
equity" include but are not limited to: principles which limit the availability
of specific performance and injunctive relief; principles which limit the
availability of a remedy under certain circumstances where another remedy has
been elected; principles requiring reasonableness, good faith and fair dealing
in the performance and enforcement of an agreement by the party seeking
enforcement; principles which may permit a party to cure a material failure to
perform its obligations; and principles affording equitable defenses such as
waiver, laches and estoppel. It is possible that some of the terms of the Debt
Securities and the Indenture may not prove enforceable against the Corporation
for reasons other than those listed in this opinion letter should an actual
enforcement action
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be brought, but (subject to all the exceptions, qualifications, exclusions and
other limitations in this letter) such unenforceability would not in our opinion
prevent the holders of the Debt Securities from realizing the principal benefits
purported to be provided by the Debt Securities and the Indenture.

         We do not find it necessary for the purposes of this opinion, and
accordingly we do not purport to cover herein, the application of the securities
of "Blue Sky" laws of the various states to the Securities.

         This opinion letter is limited to the specific issues addressed herein,
and no opinion may be inferred or implied beyond that expressly stated herein.
We assume no obligation to revise or supplement this opinion should the present
laws of the State of New York, the General Corporation Law of the State of
Delaware or the federal law of the United States be changed by legislative
action, judicial decision or otherwise.

         We hereby consent to the filing of this opinion letter with the
Commission as Exhibit 5.1 to the Registration Statement. We also consent to the
reference to our firm under the heading "Legal Matters" in the Registration
Statement. In giving this consent, we do not thereby admit that we are in the
category of persons whose consent is required under Section 7 of the Securities
Act of 1933 or the rules and regulations of the Commission.

                                            Very truly yours,

                                            /s/ Kirkland & Ellis

                                            KIRKLAND & ELLIS