Exhibit 24

                               POWER OF ATTORNEY


          Each of the undersigned directors and each of the undersigned officers
of McKesson Corporation, a Delaware corporation (the "Corporation"), does hereby
constitute and appoint Ivan D. Meyerson and Nancy A. Miller, and each of them,
as his or her true and lawful attorneys-in-fact and agents, with full power of
substitution and resubstitution, for him or her and in his or her name, place
and stead in any and all capacities, to execute and deliver in his or her name
and on his or her behalf:

          (a) one or more Registration Statements (with all exhibits thereto) of
     the Corporation on Form S-4 or any other appropriate form proposed to be
     filed by the Corporation with the Securities and Exchange Commission (the
     "SEC") (including, without limitation, Registration Statements filed
     pursuant to Rule 462(b) ("Rule 462(b)") under the Securities Act of 1933,
     as amended, or any successor thereto (the "Securities Act")) for the
     purpose of registering under the Securities Act, 5,000,000 shares of Common
     Stock, par value $0.01 per share (including the associated rights to
     purchase and the issuance of Series A Junior Participating Preferred Stock
     of the Corporation, the "Common Stock") of the Corporation plus any
     additional shares of Common Stock that may be registered pursuant to Rule
     462(b);

          (b) any and all supplements and amendments (including, without
     limitation, post-effective amendments) to such Registration Statements; and

          (c) any and all other certificates, letters, reports, statements,
     applications and any other documents and instruments in connection with the
     registration of the Securities which such attorneys-in-fact and agents, or
     any one of them, deem necessary, advisable or appropriate to enable the
     Corpora  tion to comply with (i) the Securities Act, the Securities
     Exchange Act of 1934, as amended, and the other federal securities laws of
     the United States of America and the rules, regulations and  requirements
     of the SEC in respect of any thereof; (ii) the securities or Blue Sky laws
     of any state or other govern  mental subdivision of the United States of
     America; and (iii) the securities or similar applicable laws of any foreign
     jurisdiction;

 
and each of the undersigned hereby grants unto such attorneys-in-fact and
agents, and each of them, or his or her substitute or substitutes, the power and
authority to do each and every act and thing requisite and necessary to be done
in and about the premises as fully as to all intents and purposes as he or she
might or could do in person, and does hereby ratify and confirm as his or her
own acts and deeds all that such attorneys-in-fact and agents, and each of them,
or his or her substitute or substitutes, shall lawfully do or cause to be done
by virtue hereof.  Each one of such attorneys-in-fact and agents shall have, and
may exercise, all of the powers hereby conferred.

          IN WITNESS WHEREOF, the undersigned has hereunto subscribed this power
of attorney this 11th day of June 1998.



/s/  Mark A. Pulido
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Mark A. Pulido                         David S. Pottruck         
                                                                 
                                                                 
/s/ Richard H. Hawkins                                           
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Richard H. Hawkins                     Carl E. Reichardt          
                                                                  
                                                                  
/s/ Heidi E. Yodowitz                  /s/ Alan Seelenfreund      
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Heidi E. Yodowitz                      Alan Seelenfreund          
                                                                  
                                                                  
/s/ Mary G.F. Bitterman                /s/ Jane E. Shaw           
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Mary G. F. Bitterman                   Jane E. Shaw               
                                                                  
                                                                  
/s/ Tully M. Friedman                  /s/ Robert H. Waterman, Jr.
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Tully M. Friedman                      Robert H. Waterman, Jr.     


/s/ John M. Pietruski
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John M. Pietruski

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