Exhibit 5.1



                     [LETTERHEAD OF MORRISON & FOERSTER LLP]



                               September 14, 2001



Wire One Technologies
225 Long Avenue
Hillside, NJ  07205

Ladies and Gentlemen:

         We have acted as counsel to Wire One Technologies, Inc., a Delaware
corporation (the "Company"), in connection with the proposed issuance and sale
by the Company of (a) shares of its common stock, $.0001 par value (the "Common
Stock"), (b) shares of its preferred stock, $.0001 par value (the "Preferred
Stock"), and (c) warrants to purchase Common Stock or Preferred Stock (the
"Warrants" and together with the Common Stock and Preferred Stock, collectively
referred to herein as the "Securities"). The Securities are to be issued
pursuant to a Registration Statement on Form S-3 filed by the Company with the
Securities and Exchange Commission (the "Commission") on September 14, 2001 (the
"Registration Statement").

         In connection with this opinion, we have examined such corporate
records, documents and instruments of the Company (individually, a "Document"
and, collectively with the Registration Statement, the "Documents") and such
questions of law as we have deemed necessary for the purpose of rendering the
opinions set forth herein. We have also examined the Registration Statement. In
such examination, we have assumed the genuineness of all signatures and the
authenticity of all items submitted to us as originals and the conformity with
originals of all items submitted to us as copies. In making our examination of
the Documents, we have assumed that each party to one or more of the Documents
other than the Company has the power and authority (or if such party is an
individual, the capacity) to execute and deliver, and to perform and observe the
provisions of, the Documents, and has duly authorized, executed and delivered
such Documents, and that such Documents constitute the legal, valid and binding
obligations of such party.

         The opinions hereinafter expressed are subject to the following
qualifications and exceptions:

         (i)      the effect of bankruptcy, insolvency, reorganization,
                  arrangement, moratorium or other similar laws relating to or
                  affecting the rights of





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September 14, 2001
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                  creditors generally, including, without limitation, laws
                  relating to fraudulent transfers or conveyances, preferences
                  and equitable subordination;

         (ii)     limitations imposed by general principles of equity upon the
                  availability of equitable remedies or the enforcement of
                  provisions of agreements relating to the Securities, and the
                  effect of judicial decisions that have held that certain
                  provisions are unenforceable where their enforcement would
                  violate the implied covenant of good faith and fair dealing,
                  or would be commercially unreasonable, or where a default
                  under a provision of any agreement relating to the Securities
                  is not material;

         (iii)    the effect of judicial decisions that may permit the
                  introduction of extrinsic evidence to supplement the terms of
                  the Securities or to aid in the interpretation of the
                  Securities;

         (iv)     we express no opinion as to the enforceability of provisions
                  of the Securities that impose, or that are construed as
                  effectively imposing, penalties;

         (v)      the enforceability of provisions of the Securities that
                  purport to establish evidentiary standards or make
                  determinations conclusive;

         (vi)     we express no opinion as to the enforceability of any choice
                  of law provisions contained in the Securities or the
                  enforceability of any provisions that purport to establish a
                  particular court as the forum for adjudication of any
                  controversy relating to the Securities or that purport to
                  cause any party to waive or alter any right to a trial by jury
                  or that waive objection to jurisdiction;

         (vii)    except to the extent encompassed by an opinion set forth below
                  with respect to the Company, the effect on the opinions
                  expressed herein of (1) the compliance or non-compliance of
                  any party to the Documents with any law, regulation or order
                  applicable to it or (2) the legal or regulatory status or the
                  nature of the business of any such party; and

         (viii)   our opinion is based upon current statutes, rules,
                  regulations, cases and official interpretive opinions, and it
                  covers certain items that are not directly or definitively
                  addressed by such authorities.

        Based upon and subject to the foregoing, we are of the opinion that:

         1.       The Common Stock, when sold in the manner described in the
                  Registration Statement and all necessary corporate action has
                  been taken in connection therewith, will be legally and
                  validly issued, fully paid and nonassessable.






Wire One Technologies, Inc.
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         2.       The Preferred Stock, when (a) the Board of Directors of the
                  Company (the "Board") has taken all necessary corporate action
                  in connection therewith, including, without limitation the
                  issuance and establishment of terms of the Preferred Stock and
                  related matters, and the adoption of a Certificate of
                  Designation relating to the Preferred Stock (the "Certificate
                  of Designation") conforming to the General Corporation Law of
                  the State of Delaware, (b) the Certificate of Designation has
                  been filed with the Secretary of State of the State of
                  Delaware, and (c) the Preferred Stock has been sold in the
                  manner described in the Registration Statement, will be
                  legally and validly issued, fully paid and nonassessable.


          3.      With respect to the Warrants, when (a) one or more agreements
                  (incorporating the provisions as are contained in a document
                  that will be filed as an exhibit to or incorporated by
                  reference in the Registration Statement) have been duly
                  executed and delivered by the Company and a warrant agent, (b)
                  the Board has taken all necessary corporate action in
                  connection therewith, including, without limitation, approving
                  the terms of the Warrants, reserving for issuance any Common
                  Stock or Preferred Stock underlying the Warrants and adopting
                  a Certificate of Designation relating to any Preferred Stock
                  that the Warrants may be converted into conforming to the
                  General Corporation Law of the State of Delaware, (c) the
                  Warrant certificates have been executed and authenticated in
                  accordance with the terms of the appropriate agreement, (d)
                  the Certificate of Designation has been filed with the
                  Secretary of State of the State of Delaware and (e) the
                  Warrants have been issued, sold and delivered in the manner
                  and for the consideration stated in the applicable definitive
                  purchase, underwriting or similar agreement approved by the
                  Board, upon payment of the consideration therefor provided for
                  therein, the Warrants will be legal, valid and binding
                  obligations of the Company.


          In connection with our opinions expressed above, we have assumed that,
at or prior to the time of the delivery of any Security, the Registration
Statement, and any amendments thereto (including post-effective amendments) will
have been declared effective, a prospectus supplement will have been prepared
and filed with the Commission describing the Securities offered thereby, the
authorization of the Securities applicable to such Security will not have been
modified or rescinded by the Board, there will remain a sufficient number of
authorized but unissued shares under the Company's Certificate of Incorporation
to permit the issuance of any such Security, and there will not have occurred
any change in law affecting the validity or enforceability of such Security. We
have also assumed that none of the terms of any Security to be established






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subsequent to the date hereof, the issuance and delivery of such Security, nor
the compliance by the Company with the terms of such Security, will violate any
applicable federal or state law or will result in a violation of any provision
of any instrument or agreement then binding upon the Company or any restriction
imposed by any court or governmental body having jurisdiction over the Company.

         We express no opinion as to matters governed by laws of any
jurisdiction other than the following as in effect on the date hereof: the
General Corporation Law of the State of Delaware and the federal laws of the
United States of America.

         We hereby consent to the filing of this opinion with the Commission in
connection with the filing of the Registration Statement and any amendments
thereto referred to above in accordance with the requirements of Item 601(b)(5)
of Regulation S-K under the Securities Act. We also consent to the use of our
name in the related prospectus and prospectus supplement under the heading
"Legal Matters". 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, as amended.

         This opinion may be relied upon only in connection with the issuance of
Securities while the Registration Statement is in effect.



                                        Very truly yours,

                                        /s/ Morrison & Foerster LLP

                                        Morrison & Foerster LLP