================================================================================

     As filed with the Securities and Exchange Commission on April 27, 2001

                                              Registration No. 333-____________

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
                                -----------------

                      TRANSACTION SYSTEMS ARCHITECTS, INC.
             (Exact name of registrant as specified in its charter)

            Delaware                                47-0772104
  (State or other jurisdiction of         (I.R.S. Employer Identification No.)
   incorporation or organization)

                             224 South 108th Avenue
                              Omaha, Nebraska 68154
          (Address of principal executive offices, including zip code)
                                -----------------

  Transaction Systems Architects, Inc. 2000 Non-Employee Director Stock Option
                                      Plan
                            (Full title of the plan)

                              David P. Stokes, Esq.
                          General Counsel and Secretary
                      Transaction Systems Architects, Inc.
                             224 South 108th Avenue
                              Omaha, Nebraska 68514
                                 (402) 334-5101
(Name, address and telephone number, including area code, of agent for service)
<TABLE>
<CAPTION>

                         CALCULATION OF REGISTRATION FEE

    ============================= ================== ===================== ====================== ==============
                                                        Proposed Maximum      Proposed Maximum       Amount of
      Title of Securities to be     Amount to be       Offering Price Per    Aggregate Offering    Registration
            Registered              Registered (1)         Share (2)                Price               Fee
    ============================= ================== ===================== ====================== ==============
<S> <C>                           <C>                <C>                   <C>                    <C>

       Class A Common Stock,        25,000 shares          $16.6875             $417,187.50           $104.30
          $0.005 par value
    ----------------------------- ------------------ --------------------- ---------------------- --------------
</TABLE>

(1) Pursuant to Rule 416, this Registration Statement also covers any additional
shares of Class A Common Stock which may be issuable pursuant to the
antidilution provisions of the Transaction Systems Architects, Inc. 2000
Non-Employee Director Stock Option Plan.

(2)  Pursuant to Rule  457(h),  computed on the basis of the  exercise  price of
the outstanding options granted under the Transaction  Systems Architects,  Inc.
2000 Non-Employee Director Stock Option Plan.

================================================================================
<PAGE>
                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference

         Transaction Systems Architects, Inc. (the "Company") hereby
incorporates by reference in this Registration Statement the documents listed in
(a) through (d) below previously filed with the Securities and Exchange
Commission (the "Commission") under the Securities Exchange Act of 1934, as
amended (the "Exchange Act"):

                  (a)      The Company's  Quarterly  Report on Form 10-Q for the
                           fiscal quarter ended December 31, 2000.

                  (b)      The  Company's  Annual  Report  on Form  10-K for the
                           fiscal year ended September 30, 2000.

                  (c)      The Company's current report on Form 8-K dated
                           December 14, 2000, filed with the Commission on
                           December 14, 2000.

                  (d)      The description of the Company's Class A Common Stock
                           contained in the Company's registration statement on
                           Form 8-A that the Company filed on January 11, 1995,
                           including any amendment or reports that we file for
                           the purposes of updating this description.

         All documents subsequently filed with the Commission by the Company
pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the
filing of a post-effective amendment which indicates that all securities offered
hereby have been sold or which deregisters all securities then remaining unsold
shall be deemed to be incorporated herein by reference and to be a part hereof
from the dates of filing of such documents.



Item 6.  Indemnification of Directors and Officers

         Section 145 of the Delaware General Corporation Law provides for the
indemnification of officers and directors, subject to certain limitations. The
Certificate of Incorporation of the registrant expressly provides for
indemnification of an officer or director made a party or threatened to be made
a party to proceedings by reason of the fact that such person was an officer or
director. The Certificate of Incorporation also authorizes the registrant to
maintain officer and director liability insurance, and such a policy is
currently in effect.



Item 8.  Exhibits

     Exhibit
     Number
     -------

        4.1       Transaction   Systems   Architects,   Inc.  2000  Non-Employee
                  Director  Stock Option Plan  (incorporated  by reference  from
                  Exhibit  10.33  of the  Company's  Quarterly  Report  on  Form
                  10-Q/A Amendment No. 1 for the period ended June 30, 2000).
        4.2       Amended  and  Restated  Certificate  of  Incorporation  of the
                  Company,  and amendments  thereto  (incorporated  by reference
                  from  Exhibit  3.01 of the  Company's  Registration  Statement
                  No. 33-88292 on Form S-1).
        4.3       Amended and Restated Bylaws of the Company, and First
                  Amendment thereto (incorporated by reference from Exhibit 3.02
                  of the Company's Annual Report on Form 10-K for the fiscal
                  year ended September 30, 1999).
        5         Opinion of Baker & McKenzie
       23.1       Consent of Arthur Andersen LLP
       23.2       Consent of Baker & McKenzie (See Exhibit 5)
       24         Power of Attorney (included in Signature Page)


Item 9.  Undertakings


         (a)      The undersigned registrant hereby undertakes:

         (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this Registration Statement:

                  (i)      To  include  any   prospectus   required  by  Section
         10(a)(3) of the Securities Act of 1933;

                  (ii) To reflect in the prospectus any facts or events arising
         after the effective date of the Registration Statement (or the most
         recent post-effective amendment thereof) which, individually or in the
         aggregate, represent a fundamental change in the information set forth
         in the Registration Statement. Notwithstanding the foregoing, any
         increase or decrease in volume of securities offered (if the total
         dollar value of securities offered would not exceed that which was
         registered) and any deviation from the low or high end of the estimated
         maximum offering range may be reflected in the form of prospectus filed
         with the Commission pursuant to Rule 424(b) if, in the aggregate, the
         changes in volume and price represent no more than a 20% change in the
         maximum aggregate offering price set forth in the "Calculation of
         Registration Fee" table in the effective Registration Statement;

                  (iii) To include any material information with respect to the
         plan of distribution not previously disclosed in the Registration
         Statement or any material change to such information in the
         Registration Statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
Registration Statement is on Form S-3 or Form S-8, and the information required
to be included in a post-effective amendment by those paragraphs is contained in
periodic reports filed by the Registrant pursuant to Section 13 or Section 15(d)
of the Exchange Act that are incorporated by reference in the Registration
Statement.

         (2) That, for the purpose of determining any liability under the
Securities Act of 1933, each such post-effective amendment shall be deemed to be
a new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

         (b) The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

         (c) Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the registrant pursuant to the foregoing provisions, or otherwise,
the registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act of 1933 and will be governed by the
final adjudication of such issue.

<PAGE>

                                   SIGNATURES
         The Registrant. Pursuant to the requirements of the Securities Act of
1933, the registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Omaha, State of Nebraska, on this 25th day of
April, 2001.

                                        TRANSACTION SYSTEMS ARCHITECTS, INC.

                                        By: /s/William E. Fisher
                                           ------------------------------
                                           William E. Fisher, Chairman, Chief
                                           Executive Officer, and Director


                                POWER OF ATTORNEY

         We, the undersigned officers and directors of Transaction Systems
Architects, Inc., hereby severally and individually constitute and appoint
William E. Fisher, Dwight G. Hanson and David P. Stokes, and each of them, the
true and lawful attorneys and agents of each of us to execute in the name, place
and stead of each of us (individually and in any capacity stated below) any and
all amendments to this Registration Statement on Form S-8, and all instruments
necessary or advisable in connection therewith, and to file the same with the
Securities and Exchange Commission, each of said attorneys and agents to have
power to act with or without the other and to have full power and authority to
do and perform in the name and on behalf of each of the undersigned every act
whatsoever necessary or advisable to be done in the premises as fully and to all
intents and purposes as any of the undersigned might or could do in person, and
we hereby ratify and confirm our signatures as they may be signed by our said
attorneys and agents and each of them to any and all such amendments and other
instruments.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the date indicated.
<TABLE>
<CAPTION>

Name                                        Title                                     Date
----                                        -----                                     ----
<S>                                         <C>                                       <C>

/s/ William E. Fisher                       Chairman, Chief Executive                 April 25, 2001
-----------------------------               Officer and Director
   William E. Fisher

/s/ Dwight G. Hanson                        Chief Financial Officer                   April 25, 2001
-----------------------------               and Senior Vice President
   Dwight G. Hanson

/s/ Edward C. Fuxa                          Controller                                April 25, 2001
-----------------------------
   Edward C. Fuxa

/s/ Charles E. Noell, III                   Director                                  April 25, 2001
-----------------------------
   Charles E. Noell, III

/s/ Jim D. Kever                            Director                                  April 25, 2001
-----------------------------
   Jim D. Kever

/s/ Larry G. Fendley                        Director                                  April 25, 2001
-----------------------------
   Larry G. Fendley

/s/ Roger K. Alexander                      Director                                  April 25, 2001
-----------------------------
   Roger K. Alexander

/s/ Gregory J. Duman                        Director                                  April 25, 2001
-----------------------------
   Gregory J. Duman
</TABLE>


<PAGE>
                                  EXHIBIT INDEX

Exhibit
Number    Description
-------   -----------

   4.1    Transaction Systems Architects,  Inc. 2000 Non-Employee Director Stock
          Option Plan  (incorporated  by  reference  from  Exhibit  10.33 of the
          Company's  Quarterly  Report on Form  10-Q/A  Amendment  No. 1 for the
          period ended June 30, 2000).
   4.2    Amended and Restated  Certificate of Incorporation of the Company, and
          amendments thereto (incorporated by reference from Exhibit 3.01 of the
          Company's Registration Statement No. 33-88292 on Form S-1).
   4.3    Amended  and  Restated  Bylaws of the  Company,  and  First  Amendment
          thereto  (incorporated by reference from Exhibit 3.02 of the Company's
          Annual  Report on Form 10-K for the fiscal  year ended  September  30,
          1999).
    5     Opinion of Baker & McKenzie
   23.1   Consent of Arthur Andersen LLP
   23.2   Consent of Baker & McKenzie (See Exhibit 5)
   24     Power of Attorney (included in Signature Page)
[{"type": "S-8", "sequence": "1", "filename": "s8nonemployeeoptionplan.txt", "description": "S-8 NON-EMPLOYEE DIRECTOR STOCK OPTION PLAN", "secsgml_size_bytes": 16029}]
{"company-data": {"conformed-name": "TRANSACTION SYSTEMS ARCHITECTS INC", "cik": "0000935036", "assigned-sic": "7372", "irs-number": "470772104", "state-of-incorporation": "DE", "fiscal-year-end": "0930"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-59632", "film-number": "1612543"}, "business-address": {"street1": "224 SOUTH 108TH AVE", "city": "OMAHA", "state": "NE", "zip": "68154", "phone": "4023907600"}, "mail-address": {"street1": "224 SOUTH 108TH", "city": "OMAHA", "state": "NE", "zip": "68154"}}
================================================================================

     As filed with the Securities and Exchange Commission on April 27, 2001

                                              Registration No. 333-____________

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
                                -----------------

                      TRANSACTION SYSTEMS ARCHITECTS, INC.
             (Exact name of registrant as specified in its charter)

            Delaware                                47-0772104
  (State or other jurisdiction of         (I.R.S. Employer Identification No.)
   incorporation or organization)

                             224 South 108th Avenue
                              Omaha, Nebraska 68154
          (Address of principal executive offices, including zip code)
                                -----------------

  Transaction Systems Architects, Inc. 2000 Non-Employee Director Stock Option
                                      Plan
                            (Full title of the plan)

                              David P. Stokes, Esq.
                          General Counsel and Secretary
                      Transaction Systems Architects, Inc.
                             224 South 108th Avenue
                              Omaha, Nebraska 68514
                                 (402) 334-5101
(Name, address and telephone number, including area code, of agent for service)
CALCULATION OF REGISTRATION FEE

    ============================= ================== ===================== ====================== ==============
                                                        Proposed Maximum      Proposed Maximum       Amount of
      Title of Securities to be     Amount to be       Offering Price Per    Aggregate Offering    Registration
            Registered              Registered (1)         Share (2)                Price               Fee
    ============================= ================== ===================== ====================== ==============
Class A Common Stock,        25,000 shares          $16.6875             $417,187.50           $104.30
          $0.005 par value
    ----------------------------- ------------------ --------------------- ---------------------- --------------
(1) Pursuant to Rule 416, this Registration Statement also covers any additional
shares of Class A Common Stock which may be issuable pursuant to the
antidilution provisions of the Transaction Systems Architects, Inc. 2000
Non-Employee Director Stock Option Plan.

(2)  Pursuant to Rule  457(h),  computed on the basis of the  exercise  price of
the outstanding options granted under the Transaction  Systems Architects,  Inc.
2000 Non-Employee Director Stock Option Plan.

================================================================================
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference

         Transaction Systems Architects, Inc. (the "Company") hereby
incorporates by reference in this Registration Statement the documents listed in
(a) through (d) below previously filed with the Securities and Exchange
Commission (the "Commission") under the Securities Exchange Act of 1934, as
amended (the "Exchange Act"):

                  (a)      The Company's  Quarterly  Report on Form 10-Q for the
                           fiscal quarter ended December 31, 2000.

                  (b)      The  Company's  Annual  Report  on Form  10-K for the
                           fiscal year ended September 30, 2000.

                  (c)      The Company's current report on Form 8-K dated
                           December 14, 2000, filed with the Commission on
                           December 14, 2000.

                  (d)      The description of the Company's Class A Common Stock
                           contained in the Company's registration statement on
                           Form 8-A that the Company filed on January 11, 1995,
                           including any amendment or reports that we file for
                           the purposes of updating this description.

         All documents subsequently filed with the Commission by the Company
pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the
filing of a post-effective amendment which indicates that all securities offered
hereby have been sold or which deregisters all securities then remaining unsold
shall be deemed to be incorporated herein by reference and to be a part hereof
from the dates of filing of such documents.

Item 6.  Indemnification of Directors and Officers

         Section 145 of the Delaware General Corporation Law provides for the
indemnification of officers and directors, subject to certain limitations. The
Certificate of Incorporation of the registrant expressly provides for
indemnification of an officer or director made a party or threatened to be made
a party to proceedings by reason of the fact that such person was an officer or
director. The Certificate of Incorporation also authorizes the registrant to
maintain officer and director liability insurance, and such a policy is
currently in effect.

Item 8.  Exhibits

     Exhibit
     Number
     -------

        4.1       Transaction   Systems   Architects,   Inc.  2000  Non-Employee
                  Director  Stock Option Plan  (incorporated  by reference  from
                  Exhibit  10.33  of the  Company's  Quarterly  Report  on  Form
                  10-Q/A Amendment No. 1 for the period ended June 30, 2000).
        4.2       Amended  and  Restated  Certificate  of  Incorporation  of the
                  Company,  and amendments  thereto  (incorporated  by reference
                  from  Exhibit  3.01 of the  Company's  Registration  Statement
                  No. 33-88292 on Form S-1).
        4.3       Amended and Restated Bylaws of the Company, and First
                  Amendment thereto (incorporated by reference from Exhibit 3.02
                  of the Company's Annual Report on Form 10-K for the fiscal
                  year ended September 30, 1999).
        5         Opinion of Baker & McKenzie
       23.1       Consent of Arthur Andersen LLP
       23.2       Consent of Baker & McKenzie (See Exhibit 5)
       24         Power of Attorney (included in Signature Page)

Item 9.  Undertakings

         (a)      The undersigned registrant hereby undertakes:

         (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this Registration Statement:

                  (i)      To  include  any   prospectus   required  by  Section
         10(a)(3) of the Securities Act of 1933;

                  (ii) To reflect in the prospectus any facts or events arising
         after the effective date of the Registration Statement (or the most
         recent post-effective amendment thereof) which, individually or in the
         aggregate, represent a fundamental change in the information set forth
         in the Registration Statement. Notwithstanding the foregoing, any
         increase or decrease in volume of securities offered (if the total
         dollar value of securities offered would not exceed that which was
         registered) and any deviation from the low or high end of the estimated
         maximum offering range may be reflected in the form of prospectus filed
         with the Commission pursuant to Rule 424(b) if, in the aggregate, the
         changes in volume and price represent no more than a 20% change in the
         maximum aggregate offering price set forth in the "Calculation of
         Registration Fee" table in the effective Registration Statement;

                  (iii) To include any material information with respect to the
         plan of distribution not previously disclosed in the Registration
         Statement or any material change to such information in the
         Registration Statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
Registration Statement is on Form S-3 or Form S-8, and the information required
to be included in a post-effective amendment by those paragraphs is contained in
periodic reports filed by the Registrant pursuant to Section 13 or Section 15(d)
of the Exchange Act that are incorporated by reference in the Registration
Statement.

         (2) That, for the purpose of determining any liability under the
Securities Act of 1933, each such post-effective amendment shall be deemed to be
a new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

         (b) The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

         (c) Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the registrant pursuant to the foregoing provisions, or otherwise,
the registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act of 1933 and will be governed by the
final adjudication of such issue.
SIGNATURES
         The Registrant. Pursuant to the requirements of the Securities Act of
1933, the registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Omaha, State of Nebraska, on this 25th day of
April, 2001.

                                        TRANSACTION SYSTEMS ARCHITECTS, INC.

                                        By: /s/William E. Fisher
                                           ------------------------------
                                           William E. Fisher, Chairman, Chief
                                           Executive Officer, and Director

                                POWER OF ATTORNEY

         We, the undersigned officers and directors of Transaction Systems
Architects, Inc., hereby severally and individually constitute and appoint
William E. Fisher, Dwight G. Hanson and David P. Stokes, and each of them, the
true and lawful attorneys and agents of each of us to execute in the name, place
and stead of each of us (individually and in any capacity stated below) any and
all amendments to this Registration Statement on Form S-8, and all instruments
necessary or advisable in connection therewith, and to file the same with the
Securities and Exchange Commission, each of said attorneys and agents to have
power to act with or without the other and to have full power and authority to
do and perform in the name and on behalf of each of the undersigned every act
whatsoever necessary or advisable to be done in the premises as fully and to all
intents and purposes as any of the undersigned might or could do in person, and
we hereby ratify and confirm our signatures as they may be signed by our said
attorneys and agents and each of them to any and all such amendments and other
instruments.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the date indicated.
Name                                        Title                                     Date
----                                        -----                                     ----
/s/ William E. Fisher                       Chairman, Chief Executive                 April 25, 2001
-----------------------------               Officer and Director
   William E. Fisher

/s/ Dwight G. Hanson                        Chief Financial Officer                   April 25, 2001
-----------------------------               and Senior Vice President
   Dwight G. Hanson

/s/ Edward C. Fuxa                          Controller                                April 25, 2001
-----------------------------
   Edward C. Fuxa

/s/ Charles E. Noell, III                   Director                                  April 25, 2001
-----------------------------
   Charles E. Noell, III

/s/ Jim D. Kever                            Director                                  April 25, 2001
-----------------------------
   Jim D. Kever

/s/ Larry G. Fendley                        Director                                  April 25, 2001
-----------------------------
   Larry G. Fendley

/s/ Roger K. Alexander                      Director                                  April 25, 2001
-----------------------------
   Roger K. Alexander

/s/ Gregory J. Duman                        Director                                  April 25, 2001
-----------------------------
   Gregory J. Duman
EXHIBIT INDEX

Exhibit
Number    Description
-------   -----------

   4.1    Transaction Systems Architects,  Inc. 2000 Non-Employee Director Stock
          Option Plan  (incorporated  by  reference  from  Exhibit  10.33 of the
          Company's  Quarterly  Report on Form  10-Q/A  Amendment  No. 1 for the
          period ended June 30, 2000).
   4.2    Amended and Restated  Certificate of Incorporation of the Company, and
          amendments thereto (incorporated by reference from Exhibit 3.01 of the
          Company's Registration Statement No. 33-88292 on Form S-1).
   4.3    Amended  and  Restated  Bylaws of the  Company,  and  First  Amendment
          thereto  (incorporated by reference from Exhibit 3.02 of the Company's
          Annual  Report on Form 10-K for the fiscal  year ended  September  30,
          1999).
    5     Opinion of Baker & McKenzie
   23.1   Consent of Arthur Andersen LLP
   23.2   Consent of Baker & McKenzie (See Exhibit 5)
   24     Power of Attorney (included in Signature Page)