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                                                  EXHIBIT 8.1



February 23, 1998


Hewlett-Packard Company
3000 Hanover Street
Palo Alto, CA 94304

Ladies and Gentlemen:

This opinion is being delivered pursuant to Section 6.1(d) of the Agreement 
and Plan of Reorganization, dated as of December 29, 1997 (the 
"Reorganization Agreement"), among Hewlett-Packard Company, a California 
corporation ("Parent"), Whistler Acquisition Corporation, a Delaware 
corporation and wholly-owned subsidiary of Parent ("Merger Sub"), and 
Heartstream, Inc., a Delaware corporation (the "Company").  Pursuant to the 
Reorganization Agreement, Merger Sub will merge into the Company (the 
"Merger").

Except as otherwise provided, capitalized terms not defined herein have the 
meanings set forth in the Reorganization Agreement.  All section references, 
unless otherwise indicated, are to the Internal Revenue Code of 1986, as 
amended (the "Code").

The undersigned is counsel to Parent.  As such, and for the purpose of 
rendering this opinion, counsel has examined the originals, certified copies 
or copies otherwise identified to our satisfaction as being true copies of 
the original of the following documents (including all exhibits and schedules 
attached thereto):

     (a)  The Reorganization Agreement;

     (b)  The Registration Statement on Form S-4 to be filed on or about 
February 24, 1998 by Parent with the Securities and Exchange Commission (the 
"Registration Statement");

     (c)  Representation letters of Parent and Merger Sub and the Company 
(the "Officer's Certificates"); and

     (d)  Such other instruments and documents related to the formation, 
organization and operation of Parent, Merger Sub and the Company and related 
to the consummation of the Merger and the transactions contemplated thereby 
as we have deemed necessary or appropriate.

In connection with rendering this opinion, it has been assumed (without any 
independent investigation or review thereof) that:

     1.   Original documents (including signatures) are authentic, documents
submitted to us 


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as copies conform to the original documents, and there is (or will be prior 
to the Closing) due execution and delivery of all documents where due 
execution and delivery are a prerequisite to the effectiveness thereof;

     2.   The truth and accuracy at all relevant times, of all 
representations, warranties and statements made or agreed to by Parent, 
Merger Sub and the Company, their managements, employees, officers, directors 
and stockholders in connection with the Merger, including but not limited to 
those set forth in the Reorganization Agreement (including the exhibits) and 
the Officer's Certificates; and that all covenants contained in such 
agreements are or will be performed without waiver or breach of any material 
provision thereof; and

     3.   There is no plan or intention on the part of the Company's 
stockholders to engage in a sale, exchange, transfer, distribution, pledge or 
other disposition (including a distribution by a corporation to its 
stockholders) or any transaction which would result in a reduction of risk of 
ownership, or a direct or indirect disposition (a "Sale") of shares of Parent 
Common Stock to be received in the Merger that would reduce the Company 
stockholders' ownership of Parent Common Stock to a number of shares having 
an aggregate fair market value, as of the Effective Time, of less than fifty 
percent (50%) of the aggregate fair market value of all of the capital stock 
of the Company outstanding immediately prior to the consummation of the 
Merger. Shares of the Company capital stock which are sold, redeemed or 
disposed of in a transaction that is in contemplation of or related to the 
Merger shall be considered shares of capital stock of the Company which are 
exchanged in the Merger for shares of Parent Common Stock which are then 
disposed of pursuant to the plan.

     Based on our examination of the foregoing items and subject to the 
limitations, qualifications, assumptions and caveats set forth herein, we are 
of the opinion that:

     (a)  For federal income tax purposes, the Merger will qualify as a 
"reorganization" as defined in Section 368(a); and

     (b)  The discussion entitled "Certain Federal Income Tax Considerations" 
in the Prospectus constituting a part of the Registration Statement insofar 
as it relates to the statements of law or legal conclusions is correct in all 
material respects.

     This opinion does not address the various state, local or foreign tax 
consequences that may result from the Merger.  In addition, no opinion is 
expressed as to any federal income tax consequences of the Merger except as 
specifically set forth herein and this opinion may not be relied upon except 
with respect to the consequences specifically discussed herein.

     No opinion is expressed as to any transaction other than the Merger as 
described in the Reorganization Agreement or to any other transaction 
whatsoever including the Merger if all the transactions in the Reorganization 
Agreement are not consummated in accordance with the terms of the 
Reorganization Agreement and without waiver of any material provision 
thereof.  To the extent any of the representations, warranties, statements 
and assumptions material to our opinion and upon which we have relied are not 
complete, correct, true and accurate in all material respects at all relevant 
times, our opinion would be adversely affected and should not be relied upon.


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     This opinion only represents our best judgment as to the federal income 
tax consequences of the Merger and is not binding on the Internal Revenue 
Service or the courts.  The conclusions are based on the Code, existing 
judicial decisions, administration regulations and published rulings.  No 
assurance can be given that future legislative, judicial or administrative 
changes would not adversely affect the accuracy of the conclusions stated 
herein.  Nevertheless, by rendering this opinion, we undertake no 
responsibility to advise you of any new developments in the application or 
interpretation of the federal income tax laws.

     This opinion may not be relied upon or utilized for any other purpose or 
by any other person or entity, and may not be distributed or otherwise made 
available to any other person or entity without our prior written consent.  
We hereby consent to the reference to this opinion in (and its filing as an 
exhibit to) the Registration Statement.

                                   Sincerely,



                                   /s/ SUSAN A. WILLIAMS
                                   -----------------------------
                                   Susan A. Williams
                                   Tax Counsel
                                   Hewlett-Packard Company
