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                                                                  EXHIBIT 10.37


                              SEPARATION AGREEMENT


         THIS SEPARATION AGREEMENT (this "Agreement") is made and dated as of
October 26, 2001, by and between S1 CORPORATION ("S1") and DANIEL H. DRECHSEL
("Employee").

         WHEREAS, Employee and S1 jointly agree that Employee shall resign from
all of his official positions with S1 and each subsidiary or affiliate of S1
effective as of March 31, 2002; and

         WHEREAS, Employee and S1 jointly agree that Employee shall terminate
his employment and service with S1 and each such subsidiary or affiliate
effective on the Last Day of Employment ("LDE"). LDE shall mean March 31, 2002;
and

         WHEREAS, Employee and S1 are parties to an employment agreement
entered into as of the 14th day of August 2000 ("Employment Agreement"); and

         WHEREAS, Employee and S1 intend for this Agreement to supercede and
replace all of Employee's rights and S1's obligations under the Employment
Agreement; and

         WHEREAS, Employee acknowledges that upon execution of this Agreement,
any right or entitlement of Employee to any severance benefits under the
Employment Agreement and/or S1's severance policies, or otherwise as a result
of Employee's resignation and the termination of his employment and service
hereunder will be and are superseded and replaced by this Agreement; and

         WHEREAS, S1 is willing to make certain payments to Employee and to
provide him with certain benefits after termination of his employment; in
accordance with the provisions of this Agreement; and

         WHEREAS, Employee is willing to forego any claim relating to the
remaining term of employment specified in his employment agreement, forego any
claim to certain compensation involved in said agreement in the form of pay,
bonus, company options and options in S1's European subsidiary, cancel certain
option contracts, and work to ensure a transition with minimal disruption to
the business and personnel involved therein; and

         WHEREAS, concurrently with the execution of this Agreement, Employee
and S1 are entering into a General Release, and a Confidentiality,
Non-Disclosure and Non-Competition Agreement (the "Confidentiality Agreement"),
which the parties desire to continue in effect after termination of Employee's
employment; and

         WHEREAS, Employee and S1 desire to set forth herein the terms and
conditions of their joint agreements regarding the resignation of Employee and
the

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termination of Employee's employment, including the effect of such termination,
subject to Employee's right to revoke this Agreement within seven days of
signing it, as provided herein; and

         WHEREAS, S1 denies any wrongdoing of any kind, including without
limitation any breach of the Employment Agreement or any other agreement
(whether oral, written or otherwise), promise, representation, or covenant.

         NOW, THEREFORE, in consideration of the mutual promises contained
herein, the receipt and adequacy of which are hereby acknowledged, the parties
hereto, intending to be legally bound, agree as follows:

         1.       Resignation and Termination of Employment. S1 and Employee
agree that the LDE shall be Employee's last day of employment with S1. Employee
hereby resigns from all of his official offices and positions with S1 and each
of its subsidiaries and affiliates, including without limitation, his position
as Chief Executive Officer of EMEA, effective upon the LDE. Employee shall take
no official action on behalf of S1 or any of its subsidiaries or affiliates nor
have any authority to bind S1 or any of its subsidiaries or affiliates after
the LDE. Employee agrees to execute and deliver to S1 and its subsidiaries and
affiliates such documents concerning his resignation and termination as may be
reasonably requested by S1 or any of its subsidiaries or affiliates from time
to time. S1 shall promptly take all actions necessary to notify any
governmental (both domestic and foreign) agencies that Employee no longer
serves as an officer, director or other official position of S1 or its
subsidiaries and affiliates. S1 shall continue Officers and Directors insurance
coverage for Employee with respect to each officer and director position he
holds at least until the LDE and, further, until such time as S1 takes the
action necessary to remove him from those positions and notifies all government
agencies, as set forth above and until such time as he is actually removed from
such positions. Employee agrees that he will, on or before the LDE, return to
S1 all equipment, supplies, documents and any other material or property
belonging to or leased by S1.

         2.       Severance Payments and Benefits; Options.

                  (a)      S1 will pay to Employee all accrued and unpaid
salary owed to him as of the LDE. S1 will also pay Employee for his accumulated
but unused vacation time, in accordance with its normal policies applicable to
executive employees. Employee will be eligible to earn an incentive bonus for
the period from the date of this Agreement through the LDE at the sole
discretion of S1's CEO.

                  (b)      Provided that Employee does not revoke this
Agreement as provided in Section 12 below, and so long as Employee is not in
material breach of the Confidentiality Agreement, upon the expiration of seven
days after Employee delivers to S1 a general release of claims dated as of the
LDE in the form of Exhibit


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A attached hereto and incorporated herein, without Employee having revoked such
release ("Seven Days After the LDE"):

                           (1)      S1 will pay to Employee severance payments
in the amount of (i) Twenty Three Thousand Four Hundred Eight Dollars and
Thirty Three Cents ($23,408.33) per month, less lawful withholdings, for a
period of twelve months following the LDE in accordance with S1's normal pay
periods, and (ii) an amount equal to one twelfth (1/12) of the the average
annual bonus paid to Employee during the preceding twenty four (24) months of
his Employment, less lawful withholdings, for a period of twelve (12) months
following the LDE in accordance with S1's normal pay periods; and

                           (2)      except with respect to the options
described in this paragraph, all unvested options held by Employee to purchase
common stock of the Company shall accelerate and be vested as of the LDE and
shall be exercisable to the extent and for the period provided in the option
agreements with respect to such options; provided, Employee agrees to surrender
to S1 for cancellation the 100,000 options to purchase common stock of S1
(including both vested and unvested options) issued on December 1, 1999 under
the S1 1997 Stock Option Plan, and having a strike price of $48.75. In
connection with such surrender and cancellation, Employee will execute and
deliver to S1 such documents as are requested by S1; and

                           (3)      S1 will reimburse Employee the actual cost
of repatriation of Employee and his immediate family from England to a location
of Employee's choice in the United States at Employee's written request;
provided that such repatriation occurs within six (6) months of the LDE, and
provided that such repatriation shall include the cost of packing and physical
move of Employee's home possessions from Employee's residence in England to a
location of Employee's choice in the United States, and the cost of coach air
travel from London, England to a location of Employee's choice in the United
States for Employee and his immediate family.

                           (4)      Notwithstanding any other provisions of
this Agreement, including without limitation the provisions of subparagraphs
2(b) (1), (2) and (3) above, if a claim is asserted against S1 or any
subsidiary or affiliate of S1 under or related to the guarantee of lease
payment made by S1 respecting the Tenancy by Employee of North House 5
Sandringham Park, Cobham, Surrey KT11 2EQ, S1 may offset amounts otherwise owed
under this Agreement against the amount of such claims.

                  (c)      Except as provided in this paragraph and except with
respect to health, dental and prescription drug insurance continuation coverage
that Employee is eligible for and timely elects to receive pursuant to the
provisions (commonly referred to as "COBRA") of Sections 601-609 of the
Employee Retirement


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Income Security Act of 1974, as amended ("ERISA"), Employee will not be
entitled to continued coverage under any employee benefit plan (as defined in
ERISA) or any other fringe benefit plan or arrangement during the Severance
Period and for all purposes of such plans and arrangements, Employee's
employment shall be considered to have terminated on the LDE. Upon submission
of paid receipts therefor S1 agrees to reimburse Employee for the actual cost
of (1) COBRA coverage for a period of twelve (12) months from the LDE, and (2)
the life insurance conversion premium for the base life insurance provided by
S1 for a period of twelve (12) months from the LDE.

                  (d)      Employee acknowledges that Employee is not otherwise
entitled to receive the payments of money provided for in this Agreement and
acknowledges that such payment of money is no admission of liability on the
part of the Company that it has done anything wrong. Employee agrees that
Employee will not seek anything further from the Company.

                  (e)      Amounts payable to or on behalf of Employee
hereunder will be treated as taxable income to him for tax purposes and, if
required by applicable law, S1 will withhold applicable federal, state and
local income taxes and social security and Medicare taxes, as applicable. For
all amounts paid to Employee prior to the earlier of (1) his repatriation (i.e.
while still resident in the UK) or (2) July 1, 2002, Company shall pay Employee
an additional amount so that, on an after-tax basis, the compensation and
benefits received by the Employee under this agreement will not be less than
the corresponding after tax amount that the Employee would have received if
such payments had not been subject to taxes other than United States federal,
state and local taxes. This tax equalization protection extends for so long as
any expatriate-related compensation items appear on any form W-2 or 1099 issued
to Employee for the period set forth above. Specifically, it includes all
amounts paid to the employee related to his employment prior to the LDE and
such amounts as are paid to the Employee during the severance period while the
Employee is still a UK resident, subject to the following: If the Employee has
not repatriated to the United Sates prior to July 1, 2002, then only those
amounts paid prior to this date shall have tax equalization applied. Except for
the foregoing, Employee shall be solely responsible for the payment of taxes
with respect to any amount received by Employee under this Agreement.

                  (f)      S1 will provide the Employee reasonable assistance
in preparing any filings required by the Employee with Governmental Agencies
that are related to his employment or former employment with S1. This
specifically includes an S1 appointed tax consultant which S1 will retain, at
its expense, to provide tax preparation for the year's applicable to Employee's
period of residence in the United Kingdom while employed at S1, through
calendar year 2002.


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         3.       Release by Employee.

                  (a)      Release of Claims. Employee, on behalf of himself
and his heirs, executors, administrators, successors and assigns, forever
releases and discharges S1 and its subsidiaries and affiliates, and S1's and
its subsidiaries' and affiliates' respective agents, officers, employees and
directors, from and against any and all claims, damages and liabilities
whatsoever, whether known or unknown, absolute or contingent, accrued or
unaccrued, including but not limited to all claims arising from or in any way
connected with Employee's employment by S1 and the termination of Employee's
employment with S1, but excluding any claims, damages or liabilities associated
with (i) benefits payable under the express terms of any employee benefit plan
maintained by S1 or its subsidiaries or affiliates or (ii) any breach by S1 of
the terms of this Agreement. This release includes, but is not limited to,
claims of: (1) wrongful discharge, including claims of retaliatory discharge;
(2) breach of contract; (3) discrimination on account of race, color, religion,
sex, national origin, age, disability or other illegal basis, including but not
limited to the Age Discrimination in Employment Act of 1967, as amended; (4)
violation of ERISA and (5) any claim based upon tort, equity or any violation
of any state or federal statute or municipal employment law, regulation,
executive order or other requirement. This release covers both claims Employee
knows about and those he may not know about, but does not waive or release any
claims or rights Employee may have that arise after Employee executes this
Agreement. Employee also agrees not to file any claim or lawsuit seeking
monetary recovery and asserting any claims that are released in this Section
3(a). Employee further hereby irrevocably and unconditionally waives any and
all rights to receive any relief or damages concerning any claims that are
released in this Section 3(a).

                  (b)      Employee's Acknowledgements. Employee acknowledges
that he has been advised to, and has had an opportunity to, consult with an
attorney of his choosing and at his expense before executing this Agreement,
that he has had a sufficient opportunity to read and understand the terms of
this Agreement, that he has read and does understand such terms and that he is
executing this Agreement voluntarily and without coercion. Employee further
acknowledges that he has been offered a period of at least 21 days (through
October 27, 2001) to consider this Agreement, but has voluntarily decided to
execute this Agreement before the end of such 21-day period and that this
Agreement shall become irrevocable following the seven-day period described in
Section 12 below. The parties agree that nothing contained in this Agreement
shall constitute or be treated as an admission of liability or wrongdoing by S1
or Employee.

         4.       Confidentiality and Nondisparagement. Employee agrees that he
has not provided and will not in the future provide, directly or indirectly, to
any person or entity any information that concerns or relates to the
negotiation of or the terms and conditions hereof except (i) to the extent that
such disclosure is specifically required by law or legal process or is
authorized in writing by S1; (ii) to his tax


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advisors as may be necessary for the preparation of tax returns or other
reports required by law; (iii) to his attorneys as may be necessary to secure
advice concerning this Agreement; or (iv) to members of his immediate family.
Employee agrees that before disclosing such information under parts (ii), (iii)
or (iv) of this Section 4, he will inform the recipients that they are bound by
the limitations of this Section. Employee further agrees that subsequent
disclosure of such information by any such recipients shall be deemed to be a
disclosure by him in breach of this Agreement. Employee agrees not to make any
defamatory or derogatory statements concerning any of the persons released in
Section 3(a) hereof. Employer agrees not to make any defamatory or derogatory
statements concerning the Employee.

         5.       Amendment; Modification; Waiver. No amendments or additions
to this Agreement shall be binding unless in writing and signed by both of the
parties hereto. No delay or failure at any time on the part of any party in
exercising any right, power or privilege under this Agreement, or in enforcing
any provision of this Agreement, shall impair any such right, power, or
privilege, or be construed as a waiver of any default or as any acquiescence
therein, or shall affect the right of such party thereafter to enforce each and
every provision of this Agreement in accordance with its terms.

         6.       Section Headings. The section headings used in this Agreement
are included solely for convenience and shall not affect, or be used in
connection with, the interpretation of this Agreement.

         7.       Severability. The provisions of this Agreement shall be
deemed severable and the invalidity or unenforceability of any provision shall
not affect the validity or enforceability of the other provisions hereof.

         8.       Notices. All notices, demands, requests, or other
communications which may be or are required to be given, served, or sent by any
party to any other party pursuant to this Agreement shall be in writing and
shall be hand delivered, sent by overnight courier or mailed by first-class,
registered or certified mail, return receipt requested, postage prepaid, or
transmitted by telegram, telecopy or telex, addressed as follows:


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                  If to S1:

                           S1 Corporation
                           3500 Lenox Road
                           Suite 200
                           Atlanta, GA  30326 USA
                           Fax:  +1. 404.923.6717
                           Attn: General Counsel


                  If to Employee:

                           Daniel H. Drechsel
                           17922 SW 77th Court
                           Miami, Florida 33157


                           And:

                           Jim Tenney
                           Merrit & Tenney
                           Suite 500
                           200 Galleria Parkway, NW
                           Atlanta, Georgia 30339

         Each party may designate by notice in writing a new address, to which
any notice, demand, request or communication may thereafter be so given, served
or sent. Each notice, demand, request, or communication which shall be hand
delivered, sent, mailed, telecopied or telexed in the manner described above,
or which shall be delivered to a telegraph company, shall be deemed
sufficiently given, served, sent, received or delivered for all purposes at
such time as it is delivered to the addressee (with the return receipt, the
delivery receipt, or (with respect to a telecopy or telex) the answerback being
deemed conclusive, but not exclusive, evidence of such delivery) or at such
time as delivery is refused by the addressee upon presentation.

         9.       Entire Agreement. This Agreement constitutes the entire
agreement between the parties hereto, and supersedes all prior oral or written
agreements, commitments or understandings, with respect to the matters provided
for herein, except that Employee's obligations under the Confidentiality
Agreement shall continue in full force and effect.


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         10.      Governing Law. This Agreement shall be governed by the laws
of the State of Georgia, USA applicable to contracts entered into and performed
wholly within its borders. Any action to enforce this Agreement shall be
brought in the State or Federal Courts sitting in Atlanta, Georgia USA and the
parties hereby consent to the jurisdiction thereof.

         11.      No Assignments. This Agreement is personal to each of the
parties hereto. Neither party may assign or delegate any rights or obligations
hereunder without first obtaining the written consent of the other party
hereto.

         12.      Employee's Right to Revoke within Seven Days. Employee may
revoke this Agreement by delivering a written notice of revocation to S1 in
accordance with Section 8 hereof not later than 11:59 p.m. Atlanta, Georgia
time on the seventh day after he signs and delivers this Agreement to S1 and
this Agreement shall not become effective or enforceable until such revocation
period has expired.


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         13.      Cooperation. In consideration for the compensation, stock
option vesting and other benefits provided by S1 to Employee pursuant to the
terms of this Agreement, from and after the date hereof through the fifth
anniversary of the LDE, Employee will (i) cooperate in all reasonable respects
with S1 and its affiliates and their respective directors, officers, attorneys
and experts in connection with the conduct of any action, proceeding,
investigation or litigation involving S1 or any of its affiliates, including
without limitation, that certain litigation entitled In Re S1 Corporation
Securities Litigation, Civil Action File No. 1:00-CV-1156-BBM, United States
District Court, Northern District of Georgia, Atlanta Division, and any such
action, proceeding, investigation or litigation in which Employee is called to
testify relating to matters involving facts or events relating to S1 or its
affiliates that arose during Employee's employment with S1, and (ii) promptly
respond to all reasonable requests by S1 and its affiliates relating to
information concerning S1 of which Employee may have knowledge or of which may
be in Employee's possession. S1 will, as a condition to Employee's obligations
under this Section 13, reimburse Employee for any reasonable out of pocket
expenses incurred as a result of such cooperation, provided that such expenses
have been approved in writing in advance by the Chief Executive Officer or the
Chief Financial Officer of S1. In the event that S1 and Employee agree in
writing that Employee will be required to expend a substantial amount of time
in the fulfillment of his obligations under this Section 13, S1 shall pay
Employee the sum of $1,600 per day as compensation for the devotion of such
time.

         THE PARTIES HERETO have caused this Agreement to be duly executed and
delivered in their name and on their behalf as of the date first above written.


EMPLOYEE                            S1 CORPORATION



/s/ Daniel H. Drechsel              /s/ Meigan Putnam
----------------------------        -------------------------------------------
Daniel H. Drechsel                  Name:   Meigan Putnam
                                    -------------------------------------------
                                    Title:   SVP - Global Administration
                                    -------------------------------------------