Exhibit 99.1


                                    [LOGO]
                               ---PROSPERITY---
                                BANCSHARES,INC.


PRESS RELEASE                                      For more information contact:

                                                                  David Hollaway
                                                         Chief Financial Officer
Prosperity Bancshares, Inc.(SM)                                     979.543.2200
4295 San Felipe                               davidhollaway@prosperitybanktx.com
Houston, Texas 77027                          ----------------------------------

                                                                     Dan Rollins
                                                              Investor Relations
                                                                    713.693.9300
                                                 danrollins@prosperitybanktx.com
                                                 -------------------------------



FOR IMMEDIATE RELEASE



                        PROSPERITY BANCSHARES, INC. (SM)
                        ANNOUNCES STOCK REPURCHASE PLAN



HOUSTON, September 19, 2001.  Prosperity Bancshares, Inc. (SM) (Nasdaq: PRSP),
the parent company of Prosperity Bank (SM), today announced that its Board of
Directors approved a plan to repurchase, as conditions warrant, up to $5 million
of the common stock of the Company.

David Zalman, President and CEO, stated that this stock repurchase program is
being implemented to provide management with an additional tool to enhance and
protect shareholder value.

Stock repurchases may be made from time to time on the open market or through
privately negotiated transactions.  The timing of purchases and the exact number
of shares to be purchased will depend on market conditions.  The share
repurchase program does not include specific price targets or timetables and may
be suspended at any time.  Shares repurchased in this program will be held in
treasury for reissue for various corporate purposes.  Depending on financial and
market

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conditions, the program could be terminated prior to completion.

Prosperity Bancshares, Inc.(SM), formed in 1983, is a $1.2 billion bank holding
company headquartered in Houston, Texas.  Operating under a community banking
philosophy, Prosperity seeks to develop broad customer relationships based on
service and convenience.  Prosperity offers a variety of traditional loan and
deposit products to its customers, which consist primarily of consumers and
small and medium sized businesses.  In addition to established banking products,
Prosperity offers a complete line of services including: Internet Banking
services at www.prosperitybanktx.com, Trust Services, MasterMoney Debit Cards,
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and 24 hour voice response banking.  The bank currently operates twenty-nine
(29) full service banking locations in thirteen (13) contiguous counties
including the Greater Houston Metropolitan Area.  (Angleton, Bay City, Beeville,
Clear Lake, Cleveland, Cuero, Cypress, East Bernard, Edna, El Campo, Fairfield,
Goliad, Hitchcock, Houston - Bellaire, Houston - Downtown, Houston - Medical
Center, Houston - Post Oak, Houston - River Oaks, Houston - Tanglewood, Houston
- Waugh Drive, Liberty, Magnolia, Mathis, Needville, Palacios, Sweeny, Victoria,
West Columbia, and Wharton.)


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"Safe Harbor" Statement under the Private Securities Litigation Reform Act of
1995: The statements contained in this release which are not historical facts
contain forward-looking information with respect to plans, projections or future
performance of Prosperity Bancshares, Inc. (SM) and its subsidiaries.  Forward-
looking statements, within the meaning of Section 21E of the Securities Exchange
Act of 1934, may have been made in this document. Prosperity's  results may
differ materially from those in the forward-looking statements for a variety of
reasons, including actions of competitors; changes in laws and regulations
(including changes in governmental interpretations of regulations and changes in
accounting standards); customer and consumer demand, including customer and
consumer response to marketing; effectiveness of spending, investments or
programs; fluctuations in the cost and availability of supply chain resources;
economic conditions, including currency rate fluctuations; and weather. These
factors are more fully described in Prosperity Bancshares, Inc.'s filings with
the Securities and Exchange Commission.

Copies of Prosperity Bancshares, Inc.'s (SM) SEC filings may be downloaded from
the Internet at no charge from FreeEDGAR, a real-time access to SEC filings site
located at www.freeedgar.com.
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