THIRD AMENDMENT TO CREDIT AND SECURITY AGREEMENT

                  THIS THIRD  AMENDMENT  TO CREDIT AND SECURITY  AGREEMENT  (the
"Amendment"),  dated  as of  August  __________,  1997,  is made by and  between
GATEWAY DATA SCIENCES  CORPORATION,  an Arizona  corporation  and GATEWAY CREDIT
CORPORATION, an Arizona corporation ("collectively,  the Borrower"), and NORWEST
BUSINESS CREDIT, INC., a Minnesota corporation (the "Lender").

                                    RECITALS

                  The  Borrower  and the Lender have  entered  into a Credit and
Security  Agreement  dated  as of  February  21,  1997,  as  amended  by a First
Amendment  to Credit and  Security  Agreement  dated as of April 23,  1997 and a
Second Amendment to Credit and Security  Agreement dated as of June 10, 1997 and
forbearance  letter  agreement  dated  August 8,  1997(as  so  supplemented  and
amended, the "Credit Agreement").  Capitalized terms used in these recitals have
the meanings given to them in the Credit Agreement unless otherwise specified.

                  Borrower  has  requested  that Lender  forbear for a period of
time from the exercise of its rights and remedies otherwise  available to Lender
at law, in equity, by agreement or otherwise as a result of Borrower's  defaults
under the Credit Agreement;

                  NOW,  THEREFORE,  in  consideration of the premises and of the
mutual covenants and agreements herein contained, it is agreed as follows:

                  1. Defined  Terms.  Capitalized  terms used in this  Amendment
which are  defined  in the Credit  Agreement  shall  have the same  meanings  as
defined therein, unless otherwise defined herein.

                  1.  Recitals.  The  recitals  set  forth  above  are  true and
accurate in every respect.

                  2. No Offsets. Borrower and Guarantor acknowledge with respect
to the amounts  owing to Lender that  neither  Borrower  nor  Guarantor  has any
offset, defense or counterclaim with respect thereto, no claim or defense in the
abatement  or  reduction  thereof,  nor any other claim  against  Lender or with
respect to any document  forming part of the transaction in respect of which the
Note was made or forming part of any other  transaction under which Borrower and
Guarantor are indebted to Lender.  Borrower and Guarantor  acknowledge  that all
interest imposed under the Note through the date hereof,  and all fees and other
charges that have been  collected  from or imposed upon Borrower with respect to
the  Loan  evidenced  by the Note  were and are  agreed  to,  and were  properly
computed and collected, and that Lender has fully performed all obligations that
it may have had or now has to  
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Borrower or Guarantor,  and that Lender has no obligation to make any additional
loan or extension of credit to or for the benefit of Borrower.

                  3. Acknowledgment of Default and Lender's Right to Accelerate.
Borrower  and  Guarantor  acknowledge  and agree  that (i) a  material  Event of
Default  exists and continues to exist under the Note and Loan  Documents;  (ii)
timely,  adequate and proper  notice of the  occurrence of such Event of Default
has been received by Borrower and Guarantor;  (iii) all grace  periods,  if any,
applicable  to the cure of such Event of Default  after  receipt of such  notice
have expired;  (iv) such Event of Default is continuing  without  timely cure by
Borrower;  (v) Lender has not waived in any respect such Event of Default or its
rights and  remedies  with respect  thereto;  (vi) on and as of the date hereof,
Lender has the right to accelerate and declare the indebtedness evidenced by the
Note to be  immediately  due and payable and to make  demand upon  Borrower  and
Guarantor  for  the  payment  in  full  of all  such  indebtedness;  (vii)  such
acceleration and demand for payment,  if made, would be in all respects adequate
and proper;  and (viii) Borrower and Guarantor waive any and all further notice,
presentment,  notice of  dishonor  or demand  with  respect to the  indebtedness
evidenced by the Note.

                  4.  Representations  and  Warranties  of  Borrower.  To induce
Lender to enter into this  Amendment and the  arrangement  contemplated  by this
Amendment, Borrower represents and warrants to Lender as follows:

                           (a)  The  Borrower  has  all   requisite   power  and
authority  to  execute  this  Amendment  and to perform  all of its  obligations
hereunder,  and this  Amendment  has been duly  executed  and  delivered  by the
Borrower  and  constitutes  the  legal,  valid  and  binding  obligation  of the
Borrower, enforceable in accordance with its terms.

                           (b) The  execution,  delivery and  performance by the
Borrower of this Amendment have been duly authorized by all necessary  corporate
action and do not (i)  require  any  authorization,  consent or  approval by any
governmental department,  commission,  board, bureau, agency or instrumentality,
domestic or foreign,  (ii) violate any  provision of any law, rule or regulation
or of any  order,  writ,  injunction  or  decree  presently  in  effect,  having
applicability  to the Borrower,  or the articles of  incorporation or by-laws of
the  Borrower,  or (iii) result in a breach of or constitute a default under any
indenture  or  loan  or  credit  agreement  or any  other  agreement,  lease  or
instrument to which the Borrower is a party or by which it or its properties may
be bound or affected.

                           (c)  All  of  the   representations   and  warranties
contained in Article V,  Paragraph 3 of the Credit  Agreement are correct on and
as of the date  hereof  as  though  made on and as of such  date,  except to the
extent that such  representations  and  warranties  relate  solely to an earlier
date.

                  5.  Forbearance  Period.  For  the  period  (the  "Forbearance
Period"),  commencing on the date hereof and terminating on the Termination Date
(as  hereinafter  defined),  Lender shall forbear from exercising its rights and
remedies under the Credit  
                                      -2-
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Agreement  until  after the  Termination  Date.  Because  the  Borrowers  are in
default,  pursuant to Section 4.2 of the Agreement,  Lender has no obligation to
make any further Advance. Any Advances during the Forbearance Period shall be in
the sole discretion of Lender.  For purposes hereof,  the Termination Date shall
mean the earlier of (a) a default under this Amendment or any additional Default
under  the  Credit  Agreement,  the  Note  or  any  Security  Documents,   which
termination shall be automatic, or (b) October 31, 1997.

                  6. Termination of Forbearance  Period. Upon the termination of
the Forbearance Period pursuant to Section 6 above, all forbearances,  deferrals
and  indulgences  granted by Lender shall  automatically  terminate,  and Lender
shall thereupon have, and shall be entitled to exercise,  any and all rights and
remedies which Lender may have upon the  occurrence of an Event of Default,  and
the  indebtedness  evidenced by the Credit Agreement and Note and the Note shall
become immediately due and payable, without further notice of any kind.

                  8. No Further Default. During the Forbearance Period, Borrower
shall  comply  with,  and not  violate the terms and  provisions  of, the Credit
Agreement and the Security  Documents,  all of which are incorporated  herein by
reference,  and shall fully comply with all of the terms of this  Amendment.  In
addition,  Borrower  shall  not  allow any other  Default  to occur  during  the
Forbearance  Period.  Should any additional Default occur during the Forbearance
Period,  including,  but  not  limited  to,  the  filing  of a tax  lien  by any
governmental  authority,  the Forbearance Period shall  automatically  terminate
without notice or demand.

                  9. Loan  Balance.  At no time  during the  Forbearance  Period
shall the indebtedness owed to Lender exceed  $3,000,000,  including any and all
overadvances.

                  10. Reduction of Overadvance Amount.  Borrower shall by August
22, 1997 reduce the overadvance to $750,000.  Any and all  overadvance  shall be
paid in full by September 19, 1997. Furthermore,  Borrower shall pay in full all
amounts due under the Credit Agreement on or before October 31, 1997.

                  11. Maximum  Overadvance Per Week. Between August 22, 1997 and
September 19, 1997,  the maximum  overadvance  per week shall not exceed $50,000
plus the prior week's actual total cumulative  overadvance.  For example,  as of
August 22, 1997, the total cumulative overadvance shall not exceed $750,000. For
the next week ending  August 29, 1997,  the total  overadvance  shall not exceed
$50,000 more than the actual overadvance as of the end of the prior week, but in
no event more than  $800,000.  Notwithstanding  anything to  contrary  contained
herein, the maximum  overadvance prior to the payment in full of the overadvance
on September 19, 1997 shall be no more than $950,000.
                                      -3-
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                  12. Amendment Fee.  Simultaneously  with the execution of this
Amendment,  the  Borrower  shall pay the Lender a fully  earned,  non-refundable
forbearance fee in the amount of $_______ (the "Forbearance  Fee"),  which shall
not be applied to reduce the principal indebtedness of Borrower under the Loan.

                  13.  Conditions  Precedent.  This Amendment shall be effective
when the Lender has  received an executed  original  hereof,  together  with the
Forbearance Fee.

                  14. References. All references in the Credit Agreement to "the
Credit  Agreement"  shall be deemed to refer to the Credit  Agreement as amended
hereby;  and any and all references in the Security Documents and the amendments
referred to in the Recitals  hereto to the Credit  Agreement  shall be deemed to
refer to the Credit Agreement as amended hereby.

                  15. No Waiver.  The execution of this  Amendment  shall not be
deemed to be a waiver  of any  Default  or Event of  Default  under  the  Credit
Agreement or breach,  default or event of default under any Security Document or
other  document  held by the  Lender,  whether  or not known to the  Lender  and
whether or not existing on the date of this Amendment.

                  16. Release.  The Borrower,  and each Guarantor by signing the
Acknowledgment  and  Agreement  of  Guarantors  set  forth  below,  each  hereby
absolutely and  unconditionally  releases and forever discharges the Lender, and
any  and  all  participants,   parent  corporations,   subsidiary  corporations,
affiliated corporations,  insurers, indemnitors, successors and assigns thereof,
together  with all of the present  and former  directors,  officers,  agents and
employees of any of the foregoing, from any and all claims, demands or causes of
action of any kind,  nature or description,  whether arising in law or equity or
upon contract or tort or under any state or federal law or otherwise,  which the
Borrower or such  Guarantors have had, now has or has made claim to have against
any such person for or by reason of any act,  omission,  matter,  cause or thing
whatsoever  arising from the beginning of time to and including the date of this
Amendment,  whether  such  claims,  demands  and causes of action are matured or
unmatured or known or unknown.

                  17. Costs and  Expenses.  The Borrower  hereby  reaffirms  its
agreement  under the Credit  Agreement to pay or reimburse  the Lender on demand
for all costs and expenses  incurred by the Lender in connection with the Credit
Agreement,  the Security Documents and all other documents contemplated thereby,
including  without  limitation all reasonable  fees and  disbursements  of legal
counsel.  Without  limiting  the  generality  of  the  foregoing,  the  Borrower
specifically  agrees to pay all fees and  disbursements of counsel to the Lender
for the services performed by such counsel in connection with the preparation of
this Amendment and the documents and instruments incidental hereto. The Borrower
hereby  agrees that the Lender may, at any time or from time to time in its sole
discretion and without further authorization by the Borrower, make a loan to the
Borrower under the Credit Agreement,  or apply the proceeds of any loan, for the
purpose of paying  any such  fees,  
                                      -4-
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disbursements,  costs  and  expenses  and the  Forbearance  Fee  required  under
paragraph ___ hereof.

                  18.  Counterparts.  This Amendment and the  Acknowledgment and
Agreement of Guarantors may be executed in any number of  counterparts,  each of
which when so executed  and  delivered  shall be deemed an  original  and all of
which  counterparts,   taken  together,   shall  constitute  one  and  the  same
instrument.

                  19.  Voluntary  Agreement.  Borrower,  and each  Guarantor  by
signing  the  Acknowledgment  and  Agreement  of  Guarantors  set  forth  below,
represents  and  warrants to Lender that (i) each has had an  opportunity  to be
represented by legal counsel of its choice in regard to the transaction provided
for by this Amendment;  (ii) each is fully aware and clearly  understands all of
the  terms  and  provisions   contained  in  this  Amendment;   (iii)  each  has
voluntarily,  with full  knowledge  and without  coercion or duress of any kind,
entered into this Amendment and the documents  executed in connection  with this
Amendment;   (iv)   neither   Borrower   nor   Guarantors   is  relying  on  any
representations,  either  written  or oral,  express or  implied,  made to it by
Lender  other  than as set forth in this  Amendment;  and (v) the  consideration
received  by  Borrower  and  Guarantors  to enter  into this  Amendment  and the
arrangement contemplated by this Amendment has been actual and adequate.

                  20. No Other  Changes.  Except as  explicitly  amended by this
Amendment,  all of the terms and conditions of the Credit Agreement shall remain
in full  force and  effect  and shall  apply to any  advance or letter of credit
thereunder.
                                      -5-
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                  IN WITNESS  WHEREOF,  the  parties  hereto  have  caused  this
Amendment to be duly executed as of the date first written above.

                                            BORROWER:

                                            GATEWAY DATA SCIENCES   
                                            CORPORATION, an Arizona corporation

                                            By:      /s/ Michael M. Gordon
                                               ------------------------------
                                            Name:    Michael M. Gordon
                                                 ----------------------------
                                            Title:   President
                                                  ---------------------------


                                            GATEWAY CREDIT CORPORATION, 
                                            an Arizona corporation

                                            By:      /s/ Michael M. Gordon
                                               ------------------------------
                                            Name:    Michael M. Gordon
                                                 ----------------------------
                                            Title:   President
                                                  ---------------------------


                                            LENDER:

                                            NORWEST BUSINESS CREDIT, INC.,
                                            a   Minnesota corporation

                                            By:___________________________
                                            Name:_________________________
                                            Title:________________________
                                      -6-