Exhibit 10.28

                        AMENDMENT TO EMPLOYMENT AGREEMENT

This amendment  ("Amendment") to the Employment Agreement ("Agreement") executed
between Exigent International,  Inc. and Don F. Riordan, Jr. dated June 11, 1997
is entered  into as of October  27, 1998  between  Exigent  International,  Inc.
("Exigent"),  a corporation  duly  authorized and existing under the laws of the
State of  Delaware  with a  principal  place of  business  at 1225  Evans  Road,
Melbourne,  Florida 32904 and Don F. Riordan,  Jr.  ("Employee"),  an individual
domiciled at 414 La Costa Street, Melbourne Beach, FL 32951.

NOW, THEREFORE,  for one dollar and other good and valuable  consideration,  the
receipt and  sufficiency of which is hereby mutually  acknowledged,  Exigent and
Employee hereby agree as follows:

1.   Executive  Incentive  Program for FY98(b).  Exigent and Employee agree that
     the  Executive  Incentive  Plan  Summary  for fiscal  year  1998(b)  (i.e.,
     February 1, 1998 through  December 31, 1998) attached  hereto as Attachment
     "1" of this  Amendment  shall form an  integral  part of Exhibit "B" to the
     Agreement and shall contain the parameters  for any incentive  compensation
     to be awarded to Employee in the fiscal year of 1998(b).

2.   Corporate Goals. Exigent and Employee agree that the incentive compensation
     tied to the  financial  performance  of Exigent as identified in Attachment
     "1" hereto is subject  to the  attainment  of  Employee's  corporate  goals
     described in Attachment  "2",  attached hereto and  incorporated  herein by
     this reference. One hundred (100) percent of the incentive compensation set
     forth in Attachment "1" shall be earned if and only if one hundred  percent
     of the  corporate  goals  set forth in  Attachment  "2" are  fulfilled.  An
     internal compensation committee shall be established by the CEO for Exigent
     to determine whether the corporate goals have been fulfilled.  In the event
     less than one hundred (100) percent of the corporate  goals are  fulfilled,
     the  compensation   committee  may  make  a  pro-rata  award  of  incentive
     compensation.  All  determinations by said compensation  committee shall be
     final and binding.

3.   Ratification  and Approval.  In all other  respects the Agreement is hereby
     ratified by Exigent and Employee  and remains in full force and effect,  as
     previously amended. The FY1998(b) executive compensation program supersedes
     any and all prior compensation plans in effect for FY1998(b).

IN WITNESS  WHEREOF,  this  Amendment  has been duly executed as of the date set
forth above and is retroactively effective from February 1, 1998.

For Exigent:                                        For Employee:
Exigent International, Inc.                         Don F. Riordan, Jr.


By: /s/ B.R. Smedley                                By: /s/ Don F. Riordan, Jr.
    -----------------------                             ------------------------
     B.R. "Bernie" Smedley,
     Chief Executive Officer


<PAGE>


                                                                    Attachment 1

                     Annual Executive Incentive Plan Summary
                             Chief Financial Officer

I.   Executive Target Incentive  Payments 

     Target incentive payments are based on market competitive incentive levels.
     The target incentive payment for this position is:

     |X|      CFO:  40% of base salary

II.  Incentive Plan Financial Goals and Plan Effectivity  

     Corporate and Business Unit financial goals for 1998(b) are as follows:

                                    Corporate
                           Revenue                 Earnings
                         $36 Million             $2.0 Million

          The Annual  Incentive Plan will be  implemented  only if the following
     earning  goal is met for  1998(b)  

     |X|  80% of 1998(b) corporate earnings target is met, i.e., $1.6 Million

III. Executive Incentive Plan Performance Measures and Weights 

     |X| The following table summarizes the performance  measures  applicable to
     the plan participant:

<TABLE>
<CAPTION>
   Employee       Title       Corporate Financial Goals Percentage       Business Unit Financial Goals      Individual
                                                                                   Percentage                 Goals
                                                                                                            Percentage
                            Revenue     Earnings      Share       EPS      Revenue    Operating Profit
                                                      Price                              (after tax)
<S>                <C>        <C>          <C>         <C>        <C>       <C>             <C>                <C>
Don Riordan        CFO        15%          60%         10%        10%       N/A             N/A                 5%

</TABLE>
IV.  Payout  Calculation  

     The  following  matrix will be used to establish  the payout a  participant
     will receive for Corporate,  Business Unit, or individual  performance  for
     each goal:

Level of Corporate, Business Unit,
 or Individual Performance                          Incentive Payout
---------------------------------------     ------------------------------------
Less than 80% of target performance             0% of target incentive
80% of target performance                      20% of target incentive
80% - 100% of target  performance              20% - 100% of target incentive
                                                (straight line interpolation)
100% of target  performance                    100% of target incentive
100% - 125% of target performance              100% - 125% of target incentive
                                                (straight line interpolation)
125% of target performance                     200% of target incentive

VI.  Payout Method

     |X|  Bonuses  will be paid in a  combination  of 50%  cash,  and 50%  stock
          grants.  Participants may elect for all or part of the cash portion of
          their bonus paid in stock  instead of cash.  The number of shares will
          be calculated  based on the closing stock price on the last day of the
          fiscal year

     |X|  For example,  if a $10,000 incentive payment was earned, and the stock
          price is $5.00,  the  participant  would  receive  $5,000  cash  (less
          withholding tax) and would be granted 1,000 shares of stock.


<PAGE>



                                                                    Attachment 2

                                 Corporate Goals
                          FY'98(b) Bonus Award Program
                                   Don Riordan


       FY98(b) Goals              CFO     Achieved           Comments
 CORPORATE MEASURES
  o Meet Corporate financial                        Bonus amount determined by
    objectives (based on 11                         by Company performance
    month fiscal year)                              1998(b) Exeuctive Incentive
   -   Revenue 36M (20%)          15                Incentive Program Payout
   -   Earnings 2M (60%)          60                Matrix

  o Increase Share Price                            Points will be prorated for
    from $3.125 (2/1/98)                            the percent of achieved goal
    to $5.00 (12/31/98)           10

 o  Increase Earnings Per                           Points will be prorated for
    Share (EPS) to $.39                             the percent of achieved goal
    (12/31/98)                    10

   CORPORATE TOTAL                95%

                                Individual Goals
                          FY'98(b) Bonus Award Program
                                   Don Riordan


FY98(b) Individual Goals             CFO        Achieved            Comments

QUALITY
-    On-Time SEC filings                                 Points will be prorated
-    Forms 3, 4, 5                   2.5                 for the percent of 
-    Annual Reports                                      achieved goal
-    Quarterly Reports
QUALITY TOTAL                        2.5
NEW BUSINESS DEVELOPMENT
-    Acquisitions                                        Points will be prorated
-    Complete Due Diligence &        2.5                 for the percent of
     management recommendations                          of achieved goal
     for acquisition candidates
-    Review of potential acquisition 
     candidates
-    Integration of acquired entities

   NEW BUSINESS DEV. TOTAL          2.5
   INDIVIDUAL TOTAL                  5%
   GRAND TOTAL                     100%