EXHIBIT 8.01




                          [LETTERHEAD OF ROPES & GRAY]



December 18, 2001



Brooks Automation, Inc.
15 Elizabeth Drive
Chelmsford, MA 01824


    Re:  Joint Proxy Statement of Brooks Automation Inc. and PRI
         Automation, Inc. -- Prospectus of Brooks Automation, Inc.


Ladies and Gentlemen:

      We have acted as special tax counsel to Brooks Automation, Inc. ("Brooks")
in connection with the Registration Statement on Form S-4 to which this opinion
appears as an exhibit (the "Registration Statement"), which includes the Joint
Proxy Statement of Brooks and PRI Automation, Inc. ("PRI") and the Prospectus of
Brooks (the "Proxy Statement/Prospectus"). Capitalized terms used but not
defined herein have the meanings ascribed to them in the Amended and Restated
Agreement and Plan of Merger among Brooks, PRI, and Pontiac Acquisition Corp., a
wholly owned subsidiary of Brooks, dated as of December 18, 2001 (the "Merger
Agreement").

      We have examined the Merger Agreement, pursuant to which it is
contemplated that Pontiac Acquisition Corp. will merge with and into PRI (the
"Merger"), and immediately following that merger, PRI will merge with and into
Brooks (the "Subsequent Merger," and together with the Merger, the "Mergers"),
and the Proxy Statement/Prospectus. We have assumed for purposes of the opinion
set forth below that the Mergers will be effected in accordance with the Merger
Agreement (and the Exhibits thereto), the Massachusetts Business Corporation Law
and the Delaware General Corporation Law, and as described in the Proxy
Statement/Prospectus. We have also assumed that the representation letters,
dated as of the date hereof, that PRI and Brooks have provided to us and to
Foley, Hoag & Eliot LLP, counsel to PRI (copies of which are attached hereto)
are true and accurate as of the date hereof and will remain true and accurate as
of the Effective Time. We have examined originals, or copies certified or
otherwise identified to our satisfaction, of such records, documents,
certificates or other instruments, and have made such other inquiries, as in our
judgment are necessary or appropriate

to enable us to render the opinion set forth below. We have not, however,
undertaken any independent investigation of any factual matter set forth in any
of the foregoing.

      Our opinion is based on the Internal Revenue Code of 1986, as amended (the
"Code"), Treasury Regulations, administrative interpretations and judicial
precedents as of the date hereof. If there is any subsequent change in the
applicable law or regulations, or if there are subsequently any new
administrative or judicial interpretations of the law or regulations, the
opinions expressed herein may become inapplicable.

      Subject to the foregoing and to the qualifications and limitations set
forth herein, we are of the opinion that for United States federal income tax
purposes, the Mergers will be treated as a reorganization within the meaning of
Section 368(a) of the Code.

      This opinion is intended solely for the purpose of inclusion as an exhibit
to the Registration Statement. It may not be relied upon to satisfy the
conditions set forth in Section 9.1(h) of the Merger Agreement that tax opinions
be rendered within three business days prior to the mailing of the Proxy
Statement/Prospectus and on the Closing Date, or for any other purpose, and may
not be made available to any person or entity without our prior written consent.
We hereby consent to the filing with the Securities and Exchange Commission of
this opinion as an exhibit to the Registration Statement and to the use of our
name in the section of the Proxy Statement/Prospectus entitled "Material Federal
Income Tax Considerations."

                                       Very truly yours,

                                       /s/ Ropes & Gray

                                       Ropes & Gray