August 1, 1995



Bolt Beranek and Newman Inc.
150 CambridgePark Drive
Cambridge, MA 02140

Ladies and Gentlemen:

     This opinion is furnished to you in connection with a registration
statement on Form S-8 (the "Registration Statement"), filed with the Securities
and Exchange Commission (the "Commission") under the Securities Act of 1933, as
amended, for the registration of an additional 1,200,000 shares of common stock,
$1.00 par value (the "Shares of Common Stock"), of Bolt Beranek and Newman 
Inc. (the "Company") to be issued pursuant to the Company's 1986 Stock 
Incentive Plan (the "Plan").

     We have acted as counsel for the Company in the past and are familiar with
the action taken by the Company in connection with the Plan.  For purposes of
this opinion we have examined the Plan and certain corporate records of the
Company, including its Restated Articles of Organization, its By-laws, minutes
of meetings of its Board of Directors and stockholders, and such other
documents as we deemed appropriate.

     We have made such examination of Massachusetts law as we have deemed
relevant for purposes of this opinion, but have not made any review of the laws
of any other state or jurisdiction.  
Accordingly, this opinion is limited to Massachusetts law.

     Based upon and subject to the foregoing, we are of the opinion that the
Shares of Common Stock to be issued and sold from time to time by the Company in

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accordance with the terms of the Plan will be duly authorized, validly issued,
fully paid and non-assessable.



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     We hereby consent to your filing this opinion as an exhibit to the
Registration Statement.

                              Very truly yours,

                              /s/Ropes & Gray

                              Ropes & Gray


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