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                                  EXHIBIT 4.22


             NINTH AMENDMENT TO SAVINGS AND PROFIT SHARING PLAN FOR
                 EMPLOYEES OF FIRST INTERSTATE BANCSYSTEM, INC.

     The Savings and Profit Sharing Plan for Employees of First Interstate
BancSystem, Inc. (the "Plan") is hereby amended as follows, effective August 1,
2000:

                                    ARTICLE 1

     Section 3.2 of the Plan is modified to read in its entirety as follows:

     3.2 ELIGIBILITY SERVICE. An Employee shall receive credit for one year of
Eligibility Service upon the first to occur of (a) or (b) below:

     (a)  the completion of his initial 12-month period of employment as an
          Employee, provided he has completed at least 1,000 Hours of Service
          during such 12-month period; or

     (b)  the completion of any Plan Year beginning after his Employment
          Commencement Date as an Employee during which he has completed at
          least 1,000 Hours of Service.

     In the case of Employees who were employed by First Citizens Bank of
Bozeman, Montana on January 1, 1995, Eligibility Service shall include Hours of
Service performed for First Citizens Bank of Bozeman, Montana prior to the time
it became an Affiliate. In the case of Employees who were employed by First
National Park Bank, N.A. on July 1, 1995, Eligibility Service shall include
Hours of Service performed for First National Park Bank, N.A. prior to the time
it became an Affiliate. In the case of Employees who were employed in either the
Helena, Montana or Belgrade, Montana branch of the First National Bank of
Montana on the date on which substantially all the operating assets of such
branch were acquired by Company or an Affiliate, Eligibility Service shall
include Hours of Service performed for First National Bank of Montana prior to
such date.

     For purposes of determining the Eligibility Service of an individual who is
an employee of First Interstate Bank of Wyoming, N.A., First Interstate Bank of
Montana, N.A., Mountain Bank, Security State Bank Shares, Security State Bank
and Trust Company, Equality State Bank or Equality Bankshares and Subsidiaries
on the date such organization first becomes an Affiliate, service previously
completed by the individual as an employee of either such organization
(including service for any affiliated or predecessor entity taken into account
for eligibility purposes in a qualified pension or profit sharing plan
maintained by such organization) shall be taken into account to the same extent
as service completed for an Employer.



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                                    ARTICLE 2

     Except as modified herein, all provisions of the Plan shall remain in full
force and effect.

     DATED this 30th day of August, 2000.


                                       FIRST INTERSTATE BANCSYSTEM, INC.


                                       By: /s/ ROBERT A JONES
                                           -------------------------------------
                                       Its:


                                                              "Company"



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