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                                                                       Exhibit 5

                                Hale and Dorr LLP
                               Counsellors At Law
                                 60 State Street
                                Boston, MA 02109
                           617-526-6000 - 617-526-5000


                                  April 4, 2000


Network Plus Corp.
234 Copeland Street
Quincy, MA 02169

     Re:  REGISTRATION STATEMENT ON FORM S-3

Ladies and Gentlemen:

     This opinion is furnished to you in connection with a Registration
Statement on Form S-3 (File No. 333-32042) (the "Registration Statement") filed
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Securities Act"), for the registration
of (i) 2,875,000 Depositary Shares ("Depositary Shares"), including 375,000
Depositary Shares issuable upon exercise of an over-allotment option granted by
the Company, each representing 1/10 of a share of __% Series A Cumulative
Convertible Preferred Stock, $.01 par value per share ("Series A Preferred"), of
Network Plus Corp, a Delaware corporation (the "Company"), (ii) 287,500 shares
of Series A Preferred (the "Convertible Preferred Shares"), (iii) an
indeterminate number of shares of Common Stock, $.01 par value per share, of the
Company ("Common Stock"), which may be issued in connection with the conversion
of Depositary Shares or Series A Preferred, and an indeterminate number of
shares of Common Stock which may be issued in the event that applicable
antidilution provisions with respect to the conversion of the Depositary Shares
and Series A Preferred become operative (collectively, the "Conversion Shares")
and (iv) 600,000 shares of Common Stock issuable as dividends on the Series A
Preferred (the "Dividend Shares", and collectively with the Depositary Shares,
the Convertible Preferred Shares and the Conversion Shares, the "Shares").

     The Convertible Preferred Shares, represented by the Depositary Shares, are
to be issued and sold by the Company pursuant to an underwriting agreement (the
"Underwriting Agreement") to be entered into by and among the Company and
Goldman, Sachs & Co. and Bear, Stearns & Co. Inc., as representatives of the
several underwriters named in the Underwriting Agreement, the form of which has
been filed as Exhibit 1 to the Registration Statement.

     We are acting as counsel for the Company in connection with the
registration of the Shares. We have examined signed copies of the Registration
Statement as filed with the Commission. We have also examined and relied upon
the Underwriting Agreement, minutes of


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April 4, 2000
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meetings of the stockholders and the Board of Directors of the Company as
provided to us by the Company, stock record books of the Company as provided to
us by the Company, the Certificate of Incorporation and By-Laws of the Company,
each as restated or amended to date, the form of Certificate of Designation of
the Series A Preferred, which has been filed as an exhibit to the Registration
Statement (the "Certificate of Designation"), the form of Deposit Agreement
applicable to the Depositary Shares, which has been filed as an exhibit to the
Registration Statement (the "Deposit Agreement"), and such other documents as we
have deemed necessary for purposes of rendering the opinions hereinafter set
forth.

     In our examination of the foregoing documents, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as copies, the authenticity of the originals of such latter documents and the
legal competence of all signatories to such documents.

     We assume that the appropriate action will be taken, prior to the offer and
sale of the Convertible Preferred Shares, represented by the Depositary Shares,
in accordance with the Underwriting Agreement, to register and qualify the
Shares for sale under all applicable state securities or "blue sky" laws.

     We express no opinion herein as to the laws of any state or jurisdiction
other than the state laws of the Commonwealth of Massachusetts, the General
Corporation Law of the State of Delaware and the federal laws of the United
States of America.

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

     1.   The Convertible Preferred Shares, represented by the Depositary
Shares, have been duly authorized for issuance and, when issued and paid for in
accordance with the terms and conditions of the Underwriting Agreement, will be
validly issued, fully paid and nonassessable.

     2.   The Conversion Shares have been duly authorized for issuance and, when
issued upon conversion of the Convertible Preferred Shares pursuant to the
Certificate of Designation, will be validly issued, fully paid and
nonassessable.

     3.   The Divided Shares, when authorized by the Company's Board of
Directors as payment of dividends with respect to the outstanding Convertible
Preferred Stock and issued in accordance with the Certificate of Designation,
will be duly authorized for issuance, validly issued, fully paid and
nonassessable.

     It is understood that this opinion is to be used only in connection with
the offer and sale of the Shares while the Registration Statement is in effect.

     Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters. This opinion
is based upon currently existing statutes, rules, regulations and judicial
decisions, and we disclaim any obligation to advise you of


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Network Plus Corp.
April 4, 2000
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any change in any of these sources of law or subsequent legal or factual
developments which might affect any matters or opinions set forth herein.

     We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our
name therein and in the related Prospectus under the caption "Legal Matters." In
giving such consent, we do not hereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act or the
rules and regulations of the Commission.

                                                 Very truly yours,

                                                 /s/ HALE AND DORR LLP

                                                 HALE AND DORR LLP