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                                                                   EXHIBIT 10.31

                            COLORADO MEDTECH, INC.
                               STOCK OPTION PLAN

                         (As amended October 5, 1999)

I.   Purpose
     -------

     The COLORADO MEDTECH, INC. Stock Option Plan (the "Plan") provides for the
grant of Stock Options, Stock Appreciation Rights and Supplemental Bonuses to
Employees and non-employee directors of Colorado MEDtech, Inc. (the "Company"),
and such of its subsidiaries (as defined in Section 424(f) of the Internal
Revenue Code of 1986, as amended (the "Code")) as the Board of Directors of the
Company (the "Board") shall from time to time designate ("Participating
Subsidiaries"), in order to advance the interests of the Company and its
Participating Subsidiaries through the motivation, attraction and retention of
their respective Employees and non-employee directors.

II.  Incentive Stock Options and Non-Incentive Stock Options
     -------------------------------------------------------

     The Stock Options granted under the Plan may be either:

     (a)  Incentive Stock Options ("ISOs") which are intended to be "Incentive
Stock Options" as that term is defined in Section 422 of the Code; or

     (b)  Nonstatutory Stock Options ("NSOs") which are intended to be options
that do not qualify as "Incentive Stock Options" under Section 422 of the Code.

     All Stock Options shall be ISOs unless the Option Agreement clearly
designates the Stock Options granted thereunder, or a specified portion thereof,
as NSOs.  Subject to the other provisions of the Plan, a Participant may receive
ISOs and NSOs at the same time, provided that the ISOs and NSOs are clearly
designated as such, and the exercise of one does not affect the exercise of the
other.

     Except as otherwise expressly provided herein, all of the provisions and
requirements of the Plan relating to Stock Options shall apply to ISOs and NSOs.

III. Administration
     --------------

     3.1   Committee.   The Plan shall be administered by the Board or by a
           ---------
committee composed solely of two or more directors ("Committee") each of whom is
a Non-Employee Director.  The Committee or the Board, as the case may be, shall
have full authority to administer the Plan, including authority to interpret and
construe any provision of this Plan and any Stock Option, Stock Appreciation
Right or Supplemental Bonus granted hereunder, and to adopt such rules and
regulations for administering the Plan as it may deem necessary in order to
comply with the requirements of the Code, or in order that Stock Options that
are intended to be ISOs will be classified as incentive stock options under the
Code, or in order to conform to any regulation or to any change in any law or
regulation applicable thereto.  The Committee or the Board may delegate any of
its responsibilities under this Plan, other than its responsibility to grant
Stock Options, to determine whether the Stock Appreciation Rights or
Supplemental Bonuses, if any, payable to a Participant shall be paid in cash, in
shares of Common Stock or a combination thereof, or to interpret and construe
this Plan.  The Board of Directors may reserve to

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itself any of the authority granted to the Committee as set forth herein, and it
may perform and discharge all of the functions and responsibilities of the
Committee at any time that a duly constituted Committee is not appointed and
serving. All references in this Plan to the "Committee" shall be deemed to refer
to the Board of Directors whenever the Board is discharging the powers and
responsibilities of the Committee, and to any special committee appointed by the
Board to administer particular aspects of this Plan.

     3.2   Actions of the Committee.   All actions taken and all interpretations
           ------------------------
and determinations made by the Committee in good faith (including determinations
of Fair Market Value) shall be final and binding upon all Participants, the
Company and all other interested persons.  No member of the Committee shall be
personally liable for any action, determination or interpretation made in good
faith with respect to this Plan, and all members of the Committee shall, in
addition to their rights as directors, be fully protected by the Company with
respect to any such action, determination or interpretation.  Rule 16b-3 under
the Securities Exchange Act of 1934 (the "Exchange Act") provides that the grant
of a stock option to a director or officer of a company will be exempt from the
provisions of Section 16(b) of the Exchange Act if the conditions set forth in
said Rule are satisfied.  Unless otherwise specified by the Committee, grants of
Stock Options hereunder to and exercises of Stock Options by individuals who are
officers or directors of the Company shall be made in a manner that satisfies
the conditions of said Rule.

IV.  Definitions
     -----------

     4.1   "Stock Option".   A Stock Option is the right granted under the Plan
           -------------
to purchase, at such time or times and at such price or prices ("Option Price")
as are determined by the Committee, the number of shares of Common Stock
determined by the Committee.

     4.2   "Stock Appreciation Right".  A Stock Appreciation Right is the right
           -------------------------
to receive payment, in shares of Common Stock, cash or a combination of shares
of Common Stock and cash, of the Redemption Value of a specified number of
shares of Common Stock then purchasable under a Stock Option.

     4.3   "Redemption Value".   The Redemption Value of shares of Common Stock
           -----------------
purchasable under a Stock Option shall be the amount, if any, by which the Fair
Market Value of one share of Common Stock on the date on which the Stock Option
is exercised exceeds the Option Price for such share.

     4.4   "Common Stock".   A share of Common Stock means a share of authorized
           -------------
but unissued or reacquired Common Stock (no par value per share) of the Company.

     4.5   "Fair Market Value".  If the Common Stock is not traded publicly, the
           ------------------
Fair Market Value of a share of Common Stock on any date shall be determined, in
good faith, by the Committee after such consultation with outside legal,
accounting and other experts as the Committee may deem advisable, and the
Committee shall maintain a written record of its method of determining such
value.  If the Common Stock is traded publicly, the Fair Market Value of a share
of Common Stock on any date shall be the average of the representative closing
bid and asked prices, as quoted by the National Association of Securities
Dealers through NASDAQ (its automated system for reporting quotes), for the date
in question or, if the Common Stock is listed on the NASDAQ National Market
System or is listed on a national stock exchange, the officially quoted closing
price on NASDAQ or such exchange, as the case may be, on the date in question.

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     4.6   "Employee".  An Employee is an employee of the Company or any
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Participating Subsidiary.

     4.7   "Participant".  A Participant is a person to whom a Stock Option,
           ------------
Stock Appreciation Right or Supplemental Bonus is granted.

     4.8  "Non-Employee Director".  A Non-Employee Director is a person who
          ----------------------
satisfies the definition of a "non-employee director" set forth in Rule 16b-3
under the Exchange Act or any successor rule or regulation, as it may be amended
from time to time.

     4.9   "Supplemental Bonus".  A Supplemental Bonus is the right to receive
           -------------------
payment, in shares of Common Stock, cash or a combination of shares of Common
Stock and cash, of an amount determined under Section 7.7.

V.   Eligibility and Participation
     -----------------------------

     Grants of Stock Options, Stock Appreciation Rights and Supplemental Bonuses
may be made to Employees or non-employee directors of the Company or any
Participating Subsidiary; provided, however, that only Employees, including
                          --------  -------
directors of the Company who are also Employees, shall be eligible to receive
ISOs.  The Committee shall from time to time determine the Participants to whom
Stock Options shall be granted, the number of shares of Common Stock subject to
each Stock Option to be granted, the Option Price of such Stock Options and
other terms and provisions of such Stock Options, all as provided in this Plan.
The Option Price of any ISO shall be not less than the Fair Market Value of a
share of Common Stock on the date on which the Stock Option is granted, but the
Option Price of an NSO may be less than the Fair Market Value on the date the
NSO is granted if the Committee so determines.  If an ISO is granted to an
Employee who then owns stock possessing more than 10% of the total combined
voting power of all classes of stock of the Company or any parent or subsidiary
corporation of the Company, the Option Price of such ISO shall be at least 110%
of the Fair Market Value of the Common Stock subject to the ISO at the time such
ISO is granted, and such ISO shall not be exercisable after five years after the
date on which it was granted.  Each Stock Option shall be evidenced by a written
agreement ("Option Agreement") containing such terms and provisions as the
Committee may determine, subject to the provisions of this Plan.

VI.  Shares of Common Stock Subject to the Plan
     ------------------------------------------

     6.1   Maximum Number.  The maximum aggregate number of shares of Common
           --------------
Stock that may be made subject to Stock Options shall be 4,500,000 authorized
but unissued shares.  The aggregate Fair Market Value (determined as of the time
the ISO is granted) of the Common Stock as to which all ISOs granted to an
Employee may first become exercisable in a particular calendar year may not
exceed $100,000.  If any shares of Common Stock subject to Stock Options are not
purchased or otherwise paid for before such Stock Options expire, such shares
may again be made subject to Stock Options.

     6.2   Capital Changes.  In the event any changes are made to the shares of
           ---------------
Common Stock (whether by reason of merger, consolidation, reorganization,
recapitalization, stock dividend in excess of ten percent (10%) at any single
time, stock split, combination of shares, exchange of shares, change in
corporate structure or otherwise), appropriate adjustments shall be made in: (i)
the number of shares of

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Common Stock theretofore made subject to Stock Options, and in the purchase
price of said shares; and (ii) the aggregate number of shares which may be made
subject to Stock Options. If any of the foregoing adjustments shall result in a
fractional share, the fraction shall be disregarded, and the Company shall have
no obligation to make any cash or other payment with respect to such a
fractional share.

VII. Exercise of Stock Options
     -------------------------

     7.1   Time of Exercise.  Subject to the provisions of the Plan, including
           ----------------
without limitation Section 7.5, the Committee, in its discretion, shall
determine the time when a Stock Option, or a portion of a Stock Option, shall
become exercisable, and the time when a Stock Option, or a portion of a Stock
Option, shall expire.  Such time or times shall be set forth in the Option
Agreement evidencing such Stock Option.  A Stock Option shall expire, to the
extent not exercised, no later than the tenth anniversary of the date on which
it was granted.  The Committee may accelerate the vesting of any Participant's
Stock Option by giving written notice to the Participant.  Upon receipt of such
notice, the Participant and the Company shall amend the Option Agreement to
reflect the new vesting schedule.  The acceleration of the exercise period of a
Stock Option shall not affect the expiration date of that Stock Option.

     7.2   Exchange of Outstanding Stock.  The Committee, in its sole
           -----------------------------
discretion, may permit a Participant to surrender to the Company shares of
Common Stock previously acquired by the Participant as part or full payment for
the exercise of a Stock Option.  Such surrendered shares shall be valued at
their Fair Market Value on the date of exercise.

     7.3   Use of Promissory Note; Exercise Loans.  The Committee may, in its
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sole discretion, impose terms and conditions, including conditions relating to
the manner and timing of payments, on the exercise of Stock Options.  Such terms
and conditions may include, but are not limited to, permitting a Participant to
deliver to the Company his promissory note as full or partial payment for the
exercise of a Stock Option.  The Committee, in its sole discretion, may
authorize the Company to make a loan to a Participant in connection with the
exercise of Stock Options, or authorize the Company to arrange or guarantee
loans to a Participant by a third party.

     7.4   Stock Restriction Agreement.  The Committee may provide that shares
           ---------------------------
of Common Stock issuable upon the exercise of a Stock Option shall, under
certain conditions, be subject to restrictions whereby the Company has a right
of first refusal with respect to such shares or a right or obligation to
repurchase all or a portion of such shares, which restrictions may survive a
Participant's term of employment with the Company.  The acceleration of time or
times at which a Stock Option becomes exercisable may be conditioned upon the
Participant's agreement to such restrictions.

     7.5   Termination of Employment Before Exercise.  If a Participant's
           -----------------------------------------
employment with the Company or a Participating Subsidiary shall terminate for
any reason other than the Participant's disability, any Stock Option granted to
the Participant, to the extent then exercisable under the applicable Option
Agreement(s), shall remain exercisable after the termination of his employment
for a period of 30 days (but, in the case of an ISO, in no event beyond ten
years from the date of grant of the ISO).  If the Participant's employment is
terminated because the Participant is disabled within the meaning of Section
22(e)(3) of the Code, any Stock Option granted to the Participant, to the extent
then exercisable under the applicable Option Agreement(s), shall remain
exercisable after the termination of his employment for a period of three months
(but, in the case of an ISO, in no event beyond ten years from the date of grant
of

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the ISO). If the Stock Option is not exercised during the applicable period, it
shall be deemed to have been forfeited and of no further force or effect.

      7.6   Disposition of Forfeited Stock Options.  Any shares of Common Stock
            --------------------------------------
subject to Stock Options forfeited by a Participant shall not thereafter be
eligible for purchase by the Participant but may be made subject to Stock
Options granted to other Participants.

      7.7   Grant of Supplemental Bonuses.  The Committee, either at the time of
            -----------------------------
grant or at any time prior to exercise of any Stock Option or Stock Appreciation
Right, may provide for a Supplemental Bonus from the Company or Participating
Subsidiary in connection with a specified number of shares of Common Stock then
purchasable, or which may become purchasable, under a Stock Option, or a
specified number of Stock Appreciation Rights which may be or become
exercisable.  Such Supplemental Bonus shall be payable upon the exercise of the
Stock Option or Stock Appreciation Right with regard to which such Supplemental
Bonus was granted.  A Supplemental Bonus shall not exceed the amount necessary
to reimburse the Participant for the income tax liability incurred by him upon
the exercise of the Stock Option or upon the exercise of such Stock Appreciation
Right, calculated using the maximum combined federal and applicable state income
tax rates then in effect and taking into account the tax liability arising from
the Participant's receipt of the Supplemental Bonus.  The Committee may, in its
discretion, elect to pay any part or all of the Supplemental Bonus in: (i) cash;
(ii) shares of Common Stock; or (iii) any combination of cash and shares of
Common Stock.  The provisions of Section 8.3 shall apply to the giving of
notice, the determination of the number of shares to be delivered, and the time
for delivering shares.  In applying Section 8.3, the Supplemental Bonus shall be
treated as if it were a Stock Appreciation Right that the Participant exercised
on the day the Supplemental Bonus became payable.  Shares of Common Stock issued
pursuant to this Section 7.7 shall not be deemed to have been issued upon the
exercise of a Stock Option for purposes of the limitations imposed by Section
6.1 of the Plan.

VIII. Stock Appreciation Rights
      -------------------------

      8.1   Grant of Stock Appreciation Rights.  The Committee may, from time to
            ----------------------------------
time, grant Stock Appreciation Rights to a Participant with respect to not more
than the number of shares of Common Stock which are, or may become, purchasable
under any Stock Option held by the Participant.  The Committee may, in its sole
discretion, specify the terms and conditions of such rights, including without
limitation the time period or time periods during which such rights may be
exercised and the date or dates upon which such rights shall expire and become
void and unexercisable; provided, however, that in no event shall such rights
expire and become void and unexercisable later than the time when the related
Stock Option is exercised, expires or terminates.  Each Participant to whom
Stock Appreciation Rights are granted shall be given written notice advising him
of the grant of such rights and specifying the terms and conditions of the
rights, which shall be subject to all the provisions of this Plan.

      8.2   Exercise of Stock Appreciation Rights.  Subject to Section 8.3, and
            -------------------------------------
in lieu of purchasing shares of Common Stock upon the exercise of a Stock Option
held by him, a Participant may elect to exercise the Stock Appreciation Rights,
if any, he has been granted and receive payment of the Redemption Value of all,
or any portion, of the number of shares of Common Stock subject to such Stock
Option with respect to which he has been granted Stock Appreciation Rights;
provided, however, that the Stock Appreciation Rights may be exercised only when
the Fair Market Value of the Common Stock subject to such Stock Option exceeds
the exercise price of the Stock Option.  A Participant shall exercise his Stock
Appreciation Rights by delivering a written notice to the Committee specifying
the number of

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shares with respect to which he exercises Stock Appreciation Rights and agreeing
to surrender the rights to purchase an equivalent number of shares of Common
Stock subject to his Stock Option. If a Participant exercises Stock Appreciation
Rights, payment of his Stock Appreciation Rights shall be made in accordance
with Section 8.3 on or before the 90th day after the date of exercise of the
Stock Appreciation Rights.

     8.3   Form of Payment.  If a Participant elects to exercise Stock
           ---------------
Appreciation Rights as provided in Section 8.2, the Committee may, in its
absolute discretion, elect to pay any part or all of the Redemption Value of the
shares with respect to which the Participant has exercised Stock Appreciation
Rights in: (i) cash; (ii) shares of Common Stock; or (iii) any combination of
cash and shares of Common Stock.  The Committee's election pursuant to this
Section 8.3 shall be made by giving written notice to the Participant within
said 90-day period, which notice shall specify the portion which the Committee
elects to pay in cash, shares of Common Stock or a combination thereof.  In the
event any portion is to be paid in shares of Common Stock, the number of shares
to be delivered shall be determined by dividing the amount which the Committee
elects to pay in shares of Common Stock by the Fair Market Value of one share of
Common Stock on the date of exercise of the Stock Appreciation Rights.  Any
fractional share resulting from any such calculation shall be disregarded.  Said
shares, together with any cash payable to the Participant, shall be delivered
within said 90-day period.

IX.  No Contract of Employment
     -------------------------

     Nothing in this Plan shall confer upon the Participant the right to
continue in the employ of the Company, or any Participating Subsidiary, nor
shall it interfere in any way with the right of the Company, or any such
Participating Subsidiary, to discharge the Participant at any time for any
reason whatsoever, with or without cause.  Nothing in this Article IX shall
affect any rights or obligations of the Company or any Participant under any
written contract of employment.

X.   No Rights as a Stockholder
     --------------------------

     A Participant shall have no rights as a stockholder with respect to any
shares of Common Stock subject to a Stock Option.  Except as provided in Section
6.2, no adjustment shall be made in the number of shares of Common Stock issued
to a Participant, or in any other rights of the Participant upon exercise of a
Stock Option by reason of any dividend, distribution or other right granted to
shareholders for which the record date is prior to the date of exercise of the
Participant's Stock Option.

XI.  Assignability
     -------------

     No Stock Option, Stock Appreciation Right or Supplemental Bonus right
granted under this Plan, nor any other rights acquired by a Participant under
this Plan, shall be assignable or transferable by a Participant, other than by
will or the laws of descent and distribution or, in the case of an NSO, pursuant
to a qualified domestic relations order as defined by the Code, Title I of the
Employee Retirement Income Security Act, or the rules thereunder.
Notwithstanding the preceding sentence, the Committee may, in its sole
discretion, permit the assignment or transfer of an NSO, Stock Appreciation
Right or Supplemental Bonus right granted under this Plan by a Participant, and
the exercise thereof by a person other than such Participant, on such terms and
conditions as the Committee in its sole discretion may determine.  Any such
terms shall be set forth in the Option Agreement.  In the event of a
Participant's death, the Stock Option or any Stock Appreciation Right or
Supplemental Bonus right may be exercised by the Personal

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Representative of the Participant's estate or, if no Personal Representative has
been appointed, by the successor or successors in interest determined under the
Participant's will or under the applicable laws of descent and distribution. The
terms of any rights under this Plan in the hands of a transferee or assignee
shall be determined as if held by the Participant and shall be of no greater
extent or term than if the transfer or assignment had not taken place.

XII.  Merger or Liquidation of the Company
      ------------------------------------

      If the Company or its shareholders enter into an agreement to dispose of
all, or substantially all, of the assets or outstanding capital stock of the
Company by means of a sale or liquidation, or a merger or reorganization in
which the Company is not the surviving corporation, all Stock Options
outstanding under the Plan as of the day before the consummation of such sale,
liquidation, merger or reorganization, to the extent not exercised, shall for
all purposes under this Plan become exercisable in full as of such date even
though the dates of exercise established pursuant to Section 7.1 have not yet
occurred, unless the Board shall have prescribed other terms and conditions to
the exercise of the Stock Option, or otherwise modified the Stock Options.

XIII. Amendment
      ---------

      The Board may from time to time alter, amend, suspend or discontinue the
Plan, including, where applicable, any modifications or amendments as it shall
deem advisable in order that ISOs will be classified as incentive stock options
under the Code, or in order to conform to any regulation or to any change in any
law or regulation applicable thereto; provided, however, that no such action
shall adversely affect the rights and obligations with respect to Stock Options
at any time outstanding under the Plan; and provided further that no such action
shall, without the approval of the shareholders of the Company, (i) increase the
maximum number of shares of Common Stock that may be made subject to Stock
Options (unless necessary to effect the adjustments required by Section 6.2), or
(ii) materially modify the requirements as to eligibility for participation in
the Plan.

XIV.  Registration of Optioned Shares
      -------------------------------

      The Stock Options shall not be exercisable unless the purchase of such
optioned shares is pursuant to an applicable effective registration statement
under the Securities Act of 1933, as amended (the "1933 Act"),  or unless,  in
the opinion of counsel to the Company, the proposed purchase of such optioned
shares would be exempt from the registration requirements of the 1933 Act and
from the registration or qualification requirements of applicable state
securities laws.

XV.   Withholding Taxes
      -----------------

      The Company or Participating Subsidiary may take such steps as it may deem
necessary or appropriate for the withholding of any taxes (including the
withholding of shares of Common Stock otherwise issuable which appropriate Fair
Market Value) which the Company or the Participating Subsidiary is required by
any law or regulation or any governmental authority, whether federal, state or
local, domestic or foreign, to withhold in connection with any Stock Option,
Stock Appreciation Right or Supplemental Bonus, including, but not limited to,
the withholding of all or any portion of any payment or the withholding of
issuance of shares of Common Stock to be issued upon the exercise of any Stock
Option or Stock Appreciation Right or upon payment of any Supplemental Bonus,
until the Participant

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reimburses the Company or Participating Subsidiary for the amount the Company or
Participating Subsidiary is required to withhold with respect to such taxes, or
canceling any portion of such payment or issuance in an amount sufficient to
reimburse itself for the amount it is required to so withhold.

XVI.   Brokerage Arrangements
       ----------------------

       The Committee, in its discretion, may enter into arrangements with one or
more banks, brokers or other financial institutions to facilitate the
disposition of shares acquired upon exercise of Stock Options, Stock
Appreciation Rights or Supplemental Bonuses, including, without limitation,
arrangements for the simultaneous exercise of Stock Option, Stock Appreciation
Rights or Supplemental Bonuses, and sale of the shares acquired upon such
exercise.

XVII.  Nonexclusivity of the Plan
       --------------------------

       Neither the adoption of the Plan by the Board nor the submission of this
Plan to shareholders of the Company for approval shall be construed as creating
any limitations on the power or authority of the Board to adopt such other or
additional incentive or other compensation arrangements of whatever nature as
the Board may deem necessary or desirable or preclude or limit the continuation
of any other plan, practice or arrangement for the payment of compensation or
fringe benefits to employees generally, or to any class or group of employees,
which the Company or any Participating Subsidiary now has lawfully put into
effect, including, without limitation, any retirement, pension, savings and
stock purchase plan, insurance, death and disability benefits and executive
short-term incentive plans.

XVIII. Effective Date
       --------------

     This Plan was adopted by the Board of Directors and became effective on
June 25, 1992 and was approved by the Company's shareholders on May 14, 1993.
No Stock Options shall be granted subsequent to ten years after the effective
date of the Plan.  Stock Options outstanding subsequent to ten years after the
effective date of the Plan shall continue to be governed by the provisions of
the Plan.

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