EXHIBIT 5.1
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August 15, 2002

MRO Software, Inc.
100 Crosby Drive
Bedford, MA 01730


Gentlemen:

I have assisted in the preparation of a Registration Statement on Form S-3 to be
filed with the Securities and Exchange Commission (the "Registration
Statement"), relating to 1,095,392 shares of Common Stock, $.01 par value per
share (the "Shares"), of MRO Software, Inc., a Massachusetts corporation (the
"Company"), issued in connection with (i) a certain Plan and Agreement of Merger
among the Company, a single purpose wholly-owned subsidiary of the Company named
Capri Acquisition Corp., Maincontrol, Inc., Mr. Alex Pinchev and Mr. Shai Beilis
as Shareholders' Representative dated May 28, 2002 (the "Merger Agreement").

I have examined (i) the Restated Articles of Organization and By-laws of the
Company and all amendments thereto, (ii) the Merger Agreement, and (iii) such
records of meetings of the directors and stockholders of the company, documents
and other instruments as in my judgment are necessary or appropriate to enable
me to render the opinion expressed below.

In my examination of the foregoing documents, I have assumed the genuineness of
all signatures and the authenticity of all documents submitted to me as
originals, the conformity to original documents of all documents submitted to me
as certified or photostatic copies, and the authenticity of the originals of
such latter documents.

Based upon the foregoing, I am of the opinion that the Shares have been duly
authorized for issuance and are legally issued, fully paid and nonassessable.

I hereby consent to the use of my name in the Registration Statement and consent
to the filing of this opinion with the Securities and Exchange Commission as an
exhibit to the Registration Statement.



Very truly yours,

/s/ Craig Newfield
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Craig Newfield
General Counsel