EXHIBIT 99.1

                       [PROSPERITY BANCSHARES, INC. LOGO]

PRESS RELEASE                                      For more information contact:


Prosperity Bancshares, Inc.(SM)                                      Dan Rollins
4295 San Felipe                                            Senior Vice President
Houston, Texas 77027                                                713.693.9300
                                                 danrollins@prosperitybanktx.com

FOR IMMEDIATE RELEASE


                         PROSPERITY BANCSHARES, INC.(SM)
                            COMPLETES ACQUISITION OF
                             BANK OF THE SOUTHWEST


                Houston Bank Holding Company Expands into Dallas

HOUSTON, October 1, 2002. Prosperity Bancshares, Inc. (Nasdaq: PRSP) announced
today that it has completed the acquisition of Southwest Bank Holding Company.
Southwest Bank Holding Company's subsidiary, Bank of the Southwest,
headquartered in Dallas, Texas, has become a subsidiary of Prosperity and will
continue to operate its two full service banking centers under the Bank of the
Southwest name.

On June 30, 2002, Bank of the Southwest reported total assets of $129.6 million,
total deposits of $114.3 million, total loans of $55.3 million and total
shareholders' equity of $14.7 million.

Lonnie Goodman, President and Chief Executive Officer and Cindy Swindle,
Executive Vice President and Chief Operating Officer, will continue in their
respective positions and will be working with Prosperity to further expand in
Dallas. Other officers of Bank of the Southwest include: Perry Johnson, Senior
Vice President; Jeanna "Cookie" Smith, Senior Vice President; Claudia Kingston,
Assistant Vice President; Nancy Mitchell, Assistant Vice President; Sandy
Starek, Assistant Vice President; and Luanne Reilly, Compliance Officer.

"We have been looking for opportunities to expand into North Texas for some time
and are pleased that Bank of the Southwest chose to become our partners,"
remarked David Zalman, President and Chief Executive Officer of Prosperity. "We
continue to believe that Dallas can be a great market for future expansion of
our Texas based bank. We believe that a customer focused, community minded bank
such as ours will be able to expand our presence in Dallas. We will be able to
offer Bank of the Southwest's customers a much larger lending limit than they
have had in the past."



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"Our customers will continue to enjoy the same style of personal banking they
have enjoyed with Bank of the Southwest," said Lonnie Goodman. "We are committed
to the Dallas area and are pleased to become a part of the Prosperity team. With
Prosperity's capital, we believe we are poised to become a much larger Dallas
area bank and will be able to provide our customers with more sophisticated
products and services."

Third Quarter Earnings Announcement

Prosperity has scheduled a conference call to discuss their Third Quarter
Earnings Announcement, which will be released before the market opens on Monday,
October 21, 2002, to begin at 11:00 AM, Central Time on Monday, October 21,
2002. Participants will include David Zalman, President and Chief Executive
Officer; Tim Timanus, Executive Vice President and Chief Operating Officer;
David Hollaway, CPA, Chief Financial Officer; and Dan Rollins, Senior Vice
President. Interested parties may listen live over the Internet at
www.prosperitybanktx.com or by calling 1-800-451-7724.

Prosperity Bancshares, Inc.(SM), formed in 1983, is a $1.780 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 and www.bankofthesouthwest.com,
Trust and Financial Services, Retail Brokerage Services, MasterMoney Debit
Cards, and 24 hour voice response banking. The company currently operates
forty-two (42) full service banking locations in fifteen contiguous counties
including the Greater Houston Metropolitan Area, and Dallas. (Angleton, Bay
City, Beeville, Clear Lake, Cleveland, Cuero, Cypress, Dayton, Dallas - Camp
Wisdom, Dallas - Westmoreland, East Bernard, Edna, El Campo, Fairfield,
Galveston, Goliad, Hitchcock, Houston - Aldine, Houston - Bellaire, Houston -
CityWest, Houston - Copperfield, Houston - Downtown, Houston - Gladebrook,
Houston - Highway 6, Houston - Medical Center, Houston - Memorial, Houston -
Post Oak, Houston - River Oaks, Houston - Tanglewood, Houston - Waugh Drive,
Houston - Woodcreek, Liberty, Magnolia, Mathis, Mont Belvieu, Needville,
Palacios, Sweeny, Victoria, West Columbia, Wharton and Winnie.)

"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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