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                         SUBORDINATION AGREEMENT


     This Agreement executed by Ray E. Dillon, Jr. and Ray E. Dillon, III, 
herein called "Creditors" and Northwest Business Credit, Inc., a Minnesota 
corporation, herein called the "Lender".
                                    
     Data National Corporation, a Colorado corporation ("DNC") presently owes
the Creditors $762,369.00 as evidenced by promissory notes totaling 
$551,400.00.  To induce the Lender to give credit accommodations to Service 
Business Systems, Inc. a Colorado corporation and a wholly-owned
subsidiary of DNC (the "Borrower"), which indebtedness is guarantied by DNC 
pursuant to the terms of a Guaranty By Corporation dated January 3, 1997 
(the "Guaranty"), the Creditors agree as follows:

      1.  Creditors acknowledge that the only source of payment of the 
indebtedness of DNC to either of them is as a result of dividends or other 
distributions or advances from the Borrower to DNC.  Pursuant to the Credit
and Security Agreement dated January 3, 1997 between the Borrower and the 
Lender (the "Credit Agreement"), the Borrower is prohibited from paying 
dividends or  making distributions, advances or debt repayments under certain
circumstances.  Creditors acknowledge that the Borrower has no liability with
respect to DNC's indebtedness to Creditors.  Creditors agree that if DNC 
defaults in the payment of indebtedness owed to Creditors by it, they will 
take no collection action of any kind or nature against DNC, including, 
without limitation, demand of payment of any such indebtedness, suing to 
collect any such indebtedness, or commencing or participating in the 
commencement of any bankruptcy proceeding against DNC if, at the time
thereof, an Event of Default exists under the Credit Agreement or the 
Borrower is precluded pursuant to the terms of the Credit Agreement from 
making dividends, distributions or  advances in the amount then due and
owing to Creditors.  Creditors further agree that they will not accept any 
payments from DNC in excess of the amount of the dividends, distributions, 
advances or debt repayments which the Borrower is permitted to make
pursuant to the Credit Agreement.

      2.  Creditors acknowledge that regardless of any priority otherwise 
available to Creditors by law or agreement, the Lender shall hold a first 
security interest in all collateral ( the "Collateral") of either the
Borrower or DNC securing any amounts owed by DNC to the Creditors, and any 
security interest of Creditors therein shall be and remain fully subordinated
for all purposes to the security interests of the Lender therein. 
Notwithstanding any security interest now held or hereafter acquired by 
Creditors, the Lender may take possession of, sell, dispose of, and otherwise
deal with all or any part of the Collateral, and may enforce any right or 
remedy available to it with respect to the Collateral, all without notice to 
or consent of Creditors except as specifically required by applicable law.  
The Lender shall have no duty to preserve, protect, care for, insure, take 
possession of, collect, dispose of, or otherwise realize upon any of the 
Collateral, and in no event shall the Lender be deemed the Creditors' agent 
with respect to the Collateral. All proceeds received by the Lender with 
respect to any Collateral may be applied, first, to pay or reimburse the 
Lender for all costs and expenses (including reasonable attorneys' fees) 

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incurred by the Lender in connection with the collection of such proceeds, 
and, second, to any indebtedness secured by the Lender's security interest 
in that Collateral in any order that it may choose.  Without the prior 
written consent of the Lender, Creditors will not foreclose or take any 
action against any of the Collateral until all indebtedness of the Borrower 
and DNC to the Lender has been paid in full.

      3.  Any notes or other evidence of indebtedness which have been or 
shall be issued to either Creditor by DNC shall be deposited with the Lender 
or shall be endorsed with a legend reading:

          "Payment of this instrument is subordinated to all debts 
          now or hereafter owed by maker to Norwest Business Credit, 
          Inc., pursuant to the terms of a Subordination Agreement 
          dated January 3, 1997."

      4.  Any funds or property of any kind received by either Creditor in 
violation of this Agreement shall be held in trust by such Creditor and shall
be paid or delivered to the Lender upon demand.

      5.  This Agreement shall be binding upon, and insure either to the 
benefit of, Creditors and the Lender and their respective personal 
representatives, heirs, successors and assigns.

      6.  Notice of acceptance by the Lender of this Agreement is hereby 
waived by Creditors, and this Agreement and all of the terms and provisions 
hereof shall be immediately binding upon Creditors from the date of execution
hereof.

      7.  This Agreement may be executed in counterparts, each of which shall
be deemed to be an original, but all of which together shall constitute one 
and the same instrument.

Executed this 3rd day of January, 1997.


                                                                        
BY(Signature)                           /s/Ray E. Dillon, Jr.


                                                                        
BY(Signature)                           /s/Ray E. Dillon, III