EXHIBIT 5.1

                                HALE AND DORR LLP
                               Counsellors At Law
                  60 State Street, Boston, Massachusetts 02109
                       TEL 617-526-6000 * FAX 617-526-5000


                                                           October 6, 1999


Breakaway Solutions, Inc.
50 Rowes Wharf
Boston, MA  02110

      Re:   1999 EMPLOYEE STOCK PURCHASE PLAN

Ladies and Gentlemen:

         We have assisted in the preparation of a Registration Statement on Form
S-8 (the "Registration Statement") to be filed with the Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended (the
"Securities Act"), relating to an aggregate of 400,000 shares of Common Stock,
$0.000125 par value per share (the "Shares"), of Breakaway Solutions, Inc., a
Delaware corporation (the "Company"), issuable under the Company's 1999 Employee
Stock Purchase Plan (the "Plan").

         We have examined the Certificate of Incorporation and By-Laws of the
Company, each as amended and restated to date and originals, or copies certified
to our satisfaction, of all pertinent records of the meetings of the directors
and stockholders of the Company, the Registration Statement and such other
documents relating to the Company as we have deemed material for the purposes of
this opinion.

         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 certified, photostatic or other 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 Shares in accordance with the Plan, 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
statutory provisions of 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 the
Company has duly authorized for issuance the Shares, and such Shares when issued
and paid for in accordance with the terms and conditions of the Plan, will be
validly issued, fully






Breakaway Solutions, Inc.
October 6, 1999
Page 2


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.

         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. 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