Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  CULLEN FROST BANKERS INC
 2. Date of Event Requiring Statement (Month/Day/Year)
07/02/2006		 3. Issuer Name and Ticker or Trading Symbol
SUMMIT BANCSHARES INC /TX/ [SBIT]
(Last)
(First)
(Middle)
100 WEST HOUSTON STREET		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SAN ANTONIO, TX 78205		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock, par value $1.25 0 (1) (2)
I (1) (2)
See Footnote (1) (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
CULLEN FROST BANKERS INC
100 WEST HOUSTON STREET
SAN ANTONIO, TX 78205		     X    

Signatures

/s/ Phillip D. Green, Group Vice President and Chief Financial Officer 07/11/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Cullen/Frost Bankers, Inc. ("Cullen/Frost") is filing this Form 3 solely because Cullen/Frost may be deemed a beneficial owner pursuant to Section 13(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), of 1,790,803 shares (the "Shares") of common stock of Summit Bancshares, Inc. ("Summit") that are subject to Voting Agreements, dated as of July 2, 2006, entered into by Cullen/Frost with each of Philip E. Norwood, Robert P. Evans, Elliot S. Garsek, Ronald J. Goldman, F.S. Gunn, Robert L. Hechert, Jay J. Lesok, James L. Murray, Byron B. Searcy, and Roderick D. Stepp (collectively, the "Voting Agreements") in connection with the Agreement and Plan of Merger, dated as of July 2, 2006, by and between Summit Bancshares, Inc. and Cullen/Frost Bankers, Inc. (the "Merger Agreement"). (Continued to Footnote 2)
(2) For additional information regarding the Voting Agreements and the Merger Agreement, see the Schedule 13D filed by Cullen/Frost with the Securities and Exchange Commission on the date hereof. Cullen/Frost disclaims beneficial ownership of the Shares and this filing shall not be deemed an admission that Cullen/Frost is the beneficial owner of the Shares for purposes of Section 16 of the Exchange Act or for any other purpose. Cullen/Frost has no "pecuniary interest" in the Shares.

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