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                                                                     EXHIBIT 9.1
                          [Colorado MEDtech letterhead]
June 19, 2002


Duncan Soukup
Acquisitor plc.
190 The Strand
London
England
WC2R 1JN


Dear Duncan:



You have advised us that Acquisitor plc. ("Acquisitor") and its Associates
(defined below) have acquired, and currently hold, an aggregate of 1,300,434
shares of common stock ("Shares") of Colorado MEDtech, Inc. (the "Company"). You
have expressed to us your desire to join the board of directors of the Company.
On behalf of the board of directors of the Company I invite you to join the
board of directors of the Company, subject to the agreement of you and
Acquisitor to the following terms of this letter:

1. Within seven days following the execution of this Agreement, C. Duncan Soukup
("Soukup") shall be elected to membership on the Company's board of directors.
Unless this Agreement is earlier terminated pursuant to its terms, Soukup shall
also be included in the slate of nominees recommended by the board of directors
at the 2002 annual meeting of shareholders of the Company and the Company's
proxies shall be voted in favor of Soukup. Soukup shall tender his resignation
as a director of the Company if Acquisitor ceases to own in the aggregate at
least 5% of the outstanding Voting Securities, unless the nominating committee
of the Company's board of directors requests that Soukup continue to serve on
the board. Except as provided in this Agreement, during the term of this
Agreement, Acquisitor will not seek additional representation on the Company's
board of directors unless seeking such additional representation is approved by
the nominating committee of the Company's board of directors.

2. Except as otherwise provided in this Agreement or as approved in advance by a
majority of the board of directors of the Company (with you abstaining from such
vote), during the term of this Agreement neither you nor Acquisitor will,
directly or indirectly:

   a. dispose of Voting Securities of the Company if (i) such disposition is not
   made in compliance with the policies of the Company governing the trading of
   securities of the Company on the basis of inside information which are
   applicable to all directors; or (ii) such disposition is pursuant to a
   privately-negotiated transaction and after such disposition the person that
   would acquire beneficial ownership (including, but not limited to, beneficial
   ownership as defined in Rule 13d-3 under the Securities Exchange Act of 1934,
   as amended (the "1934 Act")) of such Voting Securities would beneficially own
   more than 2% of the outstanding Voting Securities of the Company (a "2%
   Holder"); provided, however, that you may make such a disposition if you make
   the



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   Offer (described below) to the Company, the Company declines the Offer or it
   lapses, and the disposition to the 2% Holder takes place within five (5)
   business days of the lapse of or the Company's rejection of, the Offer, on
   terms no different than those contained in the Offer. "Offer" shall mean a
   written offer to sell Voting Securities to the Company and stating (i) the
   price and terms for the Voting Securities; and (ii) that it will lapse in ten
   (10) business days if not earlier accepted or rejected in writing by the
   Company.

   b. acquire ownership, or assist, advise or encourage in any way any other
   person to acquire ownership, directly or indirectly, of any of the businesses
   or assets, or any form of outstanding obligations, of the Company;

   c. solicit proxies or become a "participant" in a "solicitation" (as such
   terms are defined in Regulation 14A under the 1934 Act) in opposition to the
   recommendation of a majority of the directors of the Company (with you
   abstaining from such vote) with respect to any matter presented to
   shareholders of the Company, it being understood that the provisions of this
   Section 2(c) shall not in any way restrict the ability of Acquisitor to vote
   the Voting Securities it owns as it wishes on any such matter (except that
   Voting Securities owned by Acquisitor will, during the term of this
   Agreement, not be voted in favor of nominees not recommended by a majority of
   the board (with you abstaining from such vote) with respect to the election
   of directors of the Company));

   d. deposit Voting Securities in a voting trust, or subject such securities to
   any voting arrangement or other similar agreement with any person;

   e. otherwise act, directly or indirectly, alone or in concert with others, to
   seek to control or influence in any manner, the management, board of
   directors, policies or affairs of the Company or propose to seek to
   effectuate any form of business combination or merger with the Company or any
   affiliate thereof or any restructuring, recapitalization or similar
   transactions with respect to the Company; provided, however, that the
   foregoing shall not prevent board participation by Soukup as a director
   whether at or outside of meetings of the Company's board of directors on any
   matter;

   f. be a part of or join (by oral or written commitment) a partnership,
   syndicate or group for the purpose of acquiring, holding, or voting of Voting
   Securities or acquiring control of the Company or the conduct of its
   business;

   g. (i) engage in, or solicit any other person to engage in, a tender or
   exchange offer for Voting Securities of the Company, or (ii) advance (or
   guarantee the advance of) funds or property to assist in the purchase of
   Voting Securities by any person , or (iii) solicit the purchase of Voting
   Securities by any person (provided that sales by Acquisitor of Voting
   Securities pursuant to the proviso in Section 2(a)(ii) or in customary
   brokerage transactions effected on the Nasdaq National Market (or other
   securities market on which the Voting Securities trade) shall not be
   considered a solicitation of the purchase of Voting Securities for this
   purpose); or

   h. enter into any discussions, negotiations, arrangements or understandings
   with any person or assist any other person with respect to any of the
   foregoing.

3. The term of this Agreement shall commence on the date hereof and expire on
the earlier of (i) the day following the Company's 2003 annual meeting of
shareholders; or (ii) November



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30, 2003. In addition, this letter shall terminate immediately and be null and
void and of no further effect if (a) Soukup is not elected to the board of
directors within seven days of the execution of this letter, (b) Soukup fails to
be elected a director at the 2002 Annual Meeting of the Company's shareholders,
or (c) Soukup resigns from the board of directors due to his discovery of fraud
at the Company. Soukup shall not be removed as a director by the board of
directors prior to the earlier date specified in the first sentence of this
Section 3. If Soukup is removed as a director, this letter shall terminate
immediately and be null and void and of no further effect. If Soukup shall have
resigned other than pursuant to clause (c) of this Section 3, the restrictions
of this letter shall cease on the earlier of (I) the first day that a
shareholder of the Company would be timely in filing with the Company the notice
under Section 5 of Article I of the By-Laws of the Company (or any successor
provision) to nominate persons for election to the board of directors of the
Company or (II) the first day that a shareholder could timely comply with any
future requirements of the Company for nomination of persons for election to the
board of directors.

4. Each of Soukup, Acquisitor and the Company hereby waive any defense that an
action to enforce, or enjoin the violation of, this Agreement by specific
performance or injunctive relief is inappropriate because of an adequate remedy
at law; provided, however, that such rights to enforce this Agreement shall be
cumulative and in addition to any other remedy to which an aggrieved may be
entitled at law or equity. Acquisitor shall not be entitled to vote any Voting
Securities acquired in violation of this Agreement and the Company shall not be
entitled to challenge the acquisition, voting or holding of any Shares the
acquisition of which did not violate this Agreement or applicable law.

5. If any provision of this Agreement is found to violate any statute,
regulation, rule, order or decree of any governmental authority, court, agency
or exchange, such invalidity shall not be deemed to affect any other provision
hereof or the validity of the remainder of this Agreement and such invalid
provision shall be deemed deleted from this Agreement to the minimum extent
necessary to cure such violation.

6. As used in this Agreement,

   a. Acquisitor's "Associates" means (i) each of the persons identified as
   "Reporting Persons" on the November 14, 2001 Amendment No. 3 to the Schedule
   13D (the Schedule 13D) filed by Acquisitor plc and Amendment No. 2 to the
   Schedule 13D filed by J O Hambro Capital Management Group Limited (formerly
   known as J O Hambro Capital Management (Holdings) Limited) (Group), J O
   Hambro Capital Management Limited, American Opportunity Trust plc and
   Christopher H.B. Mills, with respect to Shares, or which are or hereafter
   become identified as Reporting Persons on any amendment of such Schedules;
   and (ii) any other person who would be deemed an "affiliate" or "associate"
   of Acquisitor, as such terms are defined in Rule 12b-2 under the 1934 Act as
   in effect on the date hereof;

   b. "person" includes an individual, corporation, limited liability company,
   joint venture or partnership, or a pension, profit sharing or other benefit
   plan or trust, or any other trust or entity of any kind;

   c. "Voting Securities" means the Shares and any other securities of the
   Company which are entitled to vote generally for the election of directors
   (or which are convertible into such securities).



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7. This Agreement may at any time be amended by a resolution adopted by a
majority of the members of the Company's Board of Directors at a meeting at
which a quorum is present (with you abstaining from such vote) and approved in
writing by Acquisitor. Neither Soukup nor Acquisitor will take any action of any
form in any court, or before any governmental or administrative tribunal or
agency, or otherwise, seeking a waiver or amendment of any of the prohibitions
contained in this letter agreement.

8. This Agreement (which constitutes the entire agreement of the parties with
respect to the subject matter hereof) shall be governed in accordance with the
laws of the State of Colorado.

   If you are in agreement with the foregoing, please sign the duplicate copy of
this letter in the space indicated below whereupon this shall constitute a
binding agreement between us.


                                          COLORADO MEDTECH, INC.


                                          By  /s/ Stephen K. Onody
                                              --------------------
                                              Chairman of the Board

AGREED AND ACCEPTED:

ACQUISITOR PLC.


By: /s/ Duncan Soukup
    ------------------------
    Title: Managing Director                              Date: 20 June 2002



    /s/ Duncan Soukup
    -------------------------
    C. Duncan Soukup                                      Date: 20 June 2002