EXHIBIT 24.1


                               POWER OF ATTORNEY

     The undersigned directors and/or officers of Ultramar Diamond Shamrock
Corporation, hereby constitute and appoint Timothy J. Fretthold, H. Pete Smith,
Curtis V. Anastasio, Todd Walker, or any of them, their true and lawful
attorneys-in-fact and agents, each with full power of substitution and
resubstitution, to do any and all acts and things in their name and behalf in
their capacity as a director and/or officer of Ultramar Diamond Shamrock
Corporation and to execute any and all instruments for them and in their name in
such capacity, which said attorneys-in-fact and agents, or any of them, may deem
necessary or advisable to enable Ultramar Diamond Shamrock Corporation to comply
with the Securities Exchange Act of 1934, as amended, and any rules, regulations
and requirements of the Securities and Exchange Commission, in connection with
the Annual Report on Form 10-K of Ultramar Diamond Shamrock Corporation for the
fiscal year ended December 31, 1998, including without limitation, power and
authority to sign for them, in their name in the capacity indicated above, such
Form 10-K and any and all amendments thereto, and to file the same, with all
exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, hereby ratifying and confirming all that the
said attorneys-in-fact and agents, or their substitute or substitutes, or any
one of them, shall do or cause to be done by virtue hereof.


/s/ R.R. Hemminghaus                         /s/ Jean Gaulin
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R. R. HEMMINGHAUS                            JEAN GAULIN

______________________________               /s/ Byron Allumbaugh
                                             ----------------------------
E. GLENN BIGGS                               BYRON ALLUMBAUGH

/s/ W. E. Bradford                           /s/ H. Frederick Christie
- ------------------------------               ----------------------------
W. E. BRADFORD                               H. FREDERICK CHRISTIE

/s/ W. H. Clark                               /s/ Russell H. Herman
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W. H. CLARK                                  RUSSELL H. HERMAN

/s/ Bob Marbut                               /s/ M. Saint-Jacques 
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BOB MARBUT                                   MADELEINE SAINT-JACQUES 

/s/ Katherine D. Ortega                      /s/ C. Barry Schaefer
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KATHERINE D. ORTEGA                          C. BARRY SCHAEFER

/s/ H. Pete Smith
- ------------------------------
H. PETE SMITH

Dated: March 3, 1999