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                                  EXHIBIT 10.9

                               AGREEMENT TO MERGE

                              SOUTHERN ARIZONA BANK

                                  WITH AND INTO

                            NATIONAL BANK OF ARIZONA

                         UNDER THE CHARTER AND TITLE OF

                            NATIONAL BANK OF ARIZONA

         THIS AGREEMENT made between Southern Arizona Bank (hereinafter referred
to as the "Bank"), an Arizona banking corporation organized under the laws of
the State of Arizona, being located in the County of Yuma, in the State of
Arizona, with a capital of $11,486,000, divided into 1,149,898 shares of common
stock, each of no par value, surplus of $3,600,000, undivided profits of
$6,894,000, and net unrealized holding gains (losses) on available-for-sale
securities, of $34,000, as of March 31, 1996, and National Bank of Arizona
(herein referred to as "NBA"), a national banking association organized under
the laws of the United States of America, being located in the County of Pima,
in the State of Arizona, with a capital of $72,887,000, divided into 150,000
shares of common stock, each of $10 par value, surplus of $30,781,000, undivided
profits of $40,306,000 and net unrealized holding gains (losses) on
available-for-sale securities, of $300,000, as of March 31, 1996, each acting
pursuant to a resolution of its Board of Directors, adopted by the vote of a
majority of its directors, pursuant to the authority given by and in accordance
with the provisions of the Act of November 7, 1918, as amended (12 U.S.C.
Section 215a) witnesseth as follows:

                                    SECTION 1

         The Bank shall be merged into NBA under the charter of the latter (the
"Merger").

                                    SECTION 2

         The name of the resulting association (hereinafter referred to as the
"Association") shall be National Bank of Arizona.

                                    SECTION 3

         The business of the Association shall be that of a national banking
association. This business shall be conducted by the Association at its main
office which shall be located at 335 North Wilmot Road, Tucson, Arizona and at
its legally established branches.
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                                    SECTION 4

         The amount of capital stock of the Association shall be $1,500,000,
divided into 150,000 shares of common stock, each of $10 par value, and at the
time the Merger shall become effective (the "Effective Date"), the Association
shall have 150,000 shares issued and outstanding for capital of $1,500,000.
Surplus of the Association will be $42,267,000, and undivided profits, including
capital reserves, when combined with the capital and surplus, will be equal to
the combined capital structures of the merging banks as stated in the preamble
to this Agreement, adjusted, however, for normal earnings and expenses between
March 31, 1996, and the Effective Date.

                                    SECTION 5

         (a) At the Effective Date, the corporate existence of the Bank and NBA
shall be merged into and continued in the Association as provided in 12 U.S.C.
Section 215a; and the Association shall be deemed to be the same corporation as
the Bank and NBA. All assets, rights, franchises and interests of the Bank and
NBA respectively, in and to every type of property (real, personal and mixed)
and choses in action, as they exist at the Effective Date, shall be transferred
to and vested in the Association by virtue of the Merger without any deed or
other transfer. At the Effective Date and without any order or other action on
the part of any court or otherwise, the Association shall hold and enjoy all
rights of property, franchises and interests, including appointments, powers,
designations and nominations, and all other rights and interests as trustee,
executor, administrator, agent, transfer agent, and registrar of stocks and
bonds, guardian of estates, assignee, receiver and conservator, and in every
other fiduciary capacity, and every agency capacity, in the same manner and to
the same extent as such rights, franchises and interests were held or enjoyed by
the Bank and NBA, respectively, immediately prior to the Effective Date.

         (b) At the Effective Date, the Association shall be liable for all
liabilities of the Bank and NBA, including liabilities arising out of the
operation of a Trust Department, and (except as so provided) all deposits,
debts, liabilities, obligations and contracts of the Bank and NBA, respectively,
matured or unmatured, whether accrued, absolute, contingent or otherwise, and
whether or not reflected or reserved against on balance sheets, books of account
or records of the Bank or NBA, as the case may be, shall be those of and are
hereby expressly assumed by the Association and shall not be released or
impaired by the Merger; and all rights of creditors and other obligees and all
liens on property of either the Bank or NBA shall be preserved unimpaired. At
the Effective Date, the Association shall be liable for all then existing
indemnification obligations of the Bank and NBA under their respective Articles
of Association or By-Laws or under any other


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agreement. At the Effective Date, the Association shall have all rights, and
shall be liable for all obligations of the Bank and NBA under all employee
compensation and benefit plans and arrangements of the Bank and NBA, and such
plans and related trusts, if any, shall continue in effect without any
interruption or termination.

                                    SECTION 6

         (a) At the Effective Date, the currently outstanding 150,000 shares of
common stock of NBA, each of $10 par value, will remain outstanding as shares of
the $10 par value common stock of the Association, and the holders of such stock
shall retain their present rights.

         (b)      No other capital stock of NBA will be issued in the
Merger.

         (c)      At the Effective Date, the shares of common stock of the
Bank shall be canceled.

                                    SECTION 7

         Between the date of this Merger Agreement and the Effective Date,
without the written consent of NBA, the Bank will not declare or distribute any
stock dividend, authorize a stock split or issue or authorize or make any
distribution of its capital stock, or merge with, consolidate with or sell its
assets to any other corporation or person, or permit any other corporation to be
merged or consolidated with it, to acquire all the assets of any other
corporation or person, or to enter into any other transaction not in the
ordinary course of the business of banking, or to dispose of any of its assets
in any other manner except in the ordinary course of business and for adequate
value.

                                    SECTION 8

         At and after the Effective Date, the Board of Directors of the
Association will be composed of the following persons:

         Hugh M. Caldwell, Jr.             James S. Lee
         Gerald J. Dent                    James H. Lundy
         John J. Gisi                      Harris H. Simmons
         Richard W. Krivel                 Roy W. Simmons

         The Board of Directors of the Association as so constituted shall serve
until the next annual meeting or until such time as their successors have been
elected and have qualified.


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                                    SECTION 9

         The Effective Date shall be the date upon which the last of the
following events shall occur:

         (a) The first to occur of (a) the date thirty days following the date
of the order of the Comptroller of the Currency (the "Comptroller") approving
the Merger, or (b) if, pursuant to section 321(b) of the Riegle Community
Development and Regulatory Improvement Act of 1994, the Comptroller shall have
prescribed a shorter period of time with the concurrence of the Attorney General
of the United States, the date on which such shorter period of time shall
elapse;

         (b) The date as of which this Agreement shall have been ratified and
confirmed by the affirmative vote of the owners of at least two-thirds of the
outstanding shares of each of the Bank and NBA; or

         (c)  Such later date as mutually agreed upon by the Presidents
of the Bank and NBA.

                                   SECTION 10

         This Agreement may be terminated by the unilateral action of the Board
of Directors of any participant prior to the approval of the shareholders of
said participant or by the mutual consent of the Boards of Directors of both
participants after any shareholder group has taken affirmative action.

                                   SECTION 11

         This Agreement shall be ratified and confirmed by the affirmative vote
of the shareholders of each of the banks owning at least two-thirds of its
capital stock outstanding, at a meeting held on the call of the Directors, or by
a consent in lieu of such a meeting; and the merger shall become effective at
the time specified in a certificate to be issued by the Comptroller, under the
seal of his office, approving the Merger.


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         WITNESS the signatures and seals of said merging banks this 21st day of
May, 1996, each hereunto set by its President and attested by its Cashier or
Secretary or Assistant Secretary, pursuant to a resolution of the Board of
Directors, acting by a majority thereof, and witness the signatures hereto of a
majority of each of said Boards of Directors.

                                              SOUTHERN ARIZONA BANK

Attest:                                       By:                             
        -----------------------                   ----------------------------
                                                         John E. Byrd
                                                         President and
                                                    Chief Executive Officer

- -------------------------------               --------------------------------
      Forrest C. Braden                               Jimmy J. Naquin

- -------------------------------               --------------------------------
        John E. Byrd                                 Colleen J. Newman

- -------------------------------               --------------------------------
       Thomas M. Howell                               Donald S. Olsen

- -------------------------------               --------------------------------
      Robert W. Kennerly                               Stephen Shadle

                           --------------------------
                              Charles Urtuzuastegui

                       Directors of Southern Arizona Bank


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STATE OF ARIZONA                    )
                                    )       ss.
COUNTY OF YUMA                      )

         On this _____ day of May, 1996, before me, a Notary Public for the
State and County aforesaid, personally came John E. Byrd, as President and Chief
Executive Officer, and Donald S. Olsen, as Secretary, of Southern Arizona Bank,
and each in his or her said capacity acknowledged the foregoing instrument to be
the act and deed of said bank and the seal affixed thereto to be its seal; and
came also:

         Forrest C. Braden             Colleen J. Newman
         Thomas M. Howell              Stephen P. Shadle
         Robert W. Kennerly            Charles Urtuzuastegui
         Jimmy J. Naquin

being a majority of the Board of Directors of said bank, and each of them
acknowledged said instrument to be the act and deed of said bank and of himself
or herself as a director thereof.

         WITNESS my official seal and signature this day and year aforesaid.

(SEAL OF NOTARY)


                                   -----------------------------------
                                   Notary Public, Yuma County
                                   My commission expires:


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                                               NATIONAL BANK OF ARIZONA



Attest:
       -----------------------                 By:
                                                  ----------------------------
                                                          John J. Gisi
                                                         President and
                                                      Chief Executive Officer

- -----------------------------                  -------------------------------
    Hugh M. Caldwell, Jr.                              James S. Lee

- -----------------------------                  -------------------------------
        Gerald J. Dent                                 James H. Lundy

- -----------------------------                  -------------------------------
         John J. Gisi                                  Harris H. Simmons

- -----------------------------                  -------------------------------
     Richard W. Krivel                                 Roy W. Simmons


                      Directors of National Bank of Arizona


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STATE OF ARIZONA          )
                          )       ss:
COUNTY OF MARICOPA        )

         On this _____ day of May, 1996, before me, a Notary Public for the
State and County aforesaid, personally came John J. Gisi as Chairman, President
and Chief Executive Officer of National Bank of Arizona, and in his said
capacity acknowledged the foregoing instrument to be the act and deed of said
association and the seal affixed thereto to be its seal; and came also:

                  James S. Lee
                  James H. Lundy

each a member of the Board of Directors of said association, and each of them
acknowledged said instrument to be the act and deed of said association and of
himself or herself as a director thereof.

         WITNESS my official seal and signature this day and year aforesaid.

(SEAL OF NOTARY)
                                      --------------------------------------
                                      Notary Public, Maricopa County 
                                      My commission expires:


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STATE OF ARIZONA    )
                    )       ss:
COUNTY OF PIMA      )

         On this _____ day of May, 1996, before me, a Notary Public for the
State and County aforesaid, personally came Hugh M. Caldwell, Jr., as Secretary
of National Bank of Arizona and a member of its Board of Directors, and in his
said capacities acknowledged the foregoing instrument to be the act and deed of
said association and the seal affixed thereto to be its seal and acknowledged
said instrument to be the act of himself as a director thereof.

         WITNESS my official seal and signature this day and year aforesaid.


(SEAL OF NOTARY)
                                         -----------------------------------
                                         Notary Public, Pima County
                                         My commission expires:


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STATE OF ARIZONA          )
                          )       ss:
COUNTY OF PIMA            )

         On this _____ day of May, 1996, before me, a Notary Public for the
State and County aforesaid, personally came Richard W. Krivel, as a member of
the Board of Directors of National Bank of Arizona, and in his said capacity
acknowledged the foregoing instrument to be the act and deed of said association
and the seal affixed thereto to be its seal and acknowledged said instrument to
be the act of himself as a director thereof.

         WITNESS my official seal and signature this day and year aforesaid.

(SEAL OF NOTARY)
                                    -----------------------------------
                                    Notary Public, Pima County
                                    My commission expires:


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STATE OF UTAH       )
                    )       ss:
COUNTY OF SALT LAKE )

         On this _____ day of May, 1996, before me, a Notary Public for the
State and County aforesaid, personally came Gerald J. Dent, Harris H. Simmons
and Roy W. Simmons, each as a member of the Board of Directors of National Bank
of Arizona, and each in his said capacity acknowledged the foregoing instrument
to be the act and deed of said association and the seal affixed thereto to be
its seal and each of them acknowledged said instrument to be the act and deed of
himself as a director thereof.

         WITNESS my official seal and signature this day and year aforesaid.

(SEAL OF NOTARY)
                                         -----------------------------------
                                         Notary Public, Salt Lake County 
                                         My commission expires:
                             
                             
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