8-A12B

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 8-A


                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934



                                PEGASYSTEMS INC.
- --------------------------------------------------------------------------------
             (Exact Name of Registrant as specified in its charter)



            MASSACHUSETTS                                04-2787865
- --------------------------------------------------------------------------------
(State of incorporation or organization)    (I.R.S. Employer Identification No.)


   101 Main Street, Cambridge, MA                           02142
- --------------------------------------------------------------------------------
(Address of principal executive offices)                   (Zip Code)


     If this Form relates to the registration of a class of debt securities and
     is effective upon filing pursuant to General Instruction A.(c)(1), please
     check the following box |_|.

     If this Form relates to the registration of a class of debt securities and
     is to become effective simultaneously with the effectiveness of a
     concurrent registration statement under the Securities Act of 1933 pursuant
     to General Instruction A.(c)(2), please check the following box |_|.


Securities to be registered pursuant to Section 12(b) of the Act:

                                      NONE

Securities to be registered pursuant to Section 12(g) of the Act:

                          Common Stock, $.01 par value





                 INFORMATION REQUIRED IN REGISTRATION STATEMENT


Item 1.  Description of Registrant's Securities to be Registered
- ----------------------------------------------------------------

         The information required by Item 202 of Regulation S-K is
included under the headings "Description of Capital Stock" in the Company's
Registration Statement on Form S-1, as amended, (File No. 333-3807) filed with
the Securities and Exchange Commission on May 15, 1996 (the "Registration
Statement on Form S-1"), which is incorporated herein by reference.

Item 2.  Exhibits
- -----------------

         The following exhibits are filed herewith (or incorporated by reference
as indicated below):

         1. A specimen copy of the certificate for shares of the Company's 
Common Stock is filed herewith.

         2.1. The Articles of Organization of the Company, as amended 
(incorporated by reference to Exhibit 3.1 of the Registration Statement on 
Form S-1).

         2.2 Form of the Restated Articles of Organization of the Company to be
effective prior to the effectiveness of the Registration Statement on Form S-1
(incorporated by reference to Exhibit 3.3 of the Registration Statement on Form
S-1).

         2.3 Form of the By-Laws of the Company (incorporated by reference to
Exhibit 3.2 of the Registration Statement on Form S- 1).

         2.4 Form of the Restated By-Laws of the Company to be effective prior
to the effectiveness of the Registration Statement on Form S-1 (incorporated by
reference to Exhibit 3.4 of the Registration Statement on Form S-1).





                                    SIGNATURE


         Pursuant to the requirements of Section 12 of the Securities Exchange
Act of 1934, the registrant has duly caused this registration statement to be
signed on its behalf by the undersigned, thereto duly authorized.


                                                       PEGASYSTEMS INC.

         By:  /s/ Alan Trefler
              ----------------------------
              Alan Trefler, President

DATED:  June 21, 1996

EX-4.1

     COMMON STOCK                                       COMMON STOCK
       NUMBER                                              SHARES
       PS-


[Pegasystems Logo]

Pegasystems Inc.

THIS CERTIFICATE IS TRANSFERABLE                         SEE REVERSE FOR
IN HARTFORD, CT AND NEW YORK, NY                        CERTAIN DEFINITIONS
                                                         CUSIP 705573 10 3

        INCORPORATED UNDER THE LAWS OF THE COMMONWEALTH OF MASSACHUSETTS

THIS CERTIFIES THAT






is the owner of

                   FULLY PAID AND NON-ASSESSABLE SHARES OF THE
                    COMMON CAPITAL STOCK, $.01 PAR VALUE, OF


                                Pegasystems Inc.

transferable only on the books of the Corporation by the holder hereof
in person or by duly authorized attorney upon surrender of this Certificate
properly endorsed. This Certificate and the shares represented hereby are
issued under and subject to the laws of the Commonwealth of Massachusetts and to
the Restated Articles of Organization and Restated Bylaws of the Corporation,
all as in effect from time to time. This certificate is not valid until
countersigned and registered by the Transfer Agent and Registrar. 

    WITNESS the facsimile seal of the Corporation and the facsimile signatures
of its duly authorized officers.

Dated:

[Signature of Alan Trefler]                          [Signature of Ira Vishner]
       PRESIDENT                                             TREASURER



                                Pegasystems Inc.
                                   Corporate
                                      SEAL
                                      1983
                                 MASSACHUSETTS
                                       *

COUNTERSIGNED AND REGISTERED:
                            FLEET NATIONAL BANK
                                                   TRANSFER AGENT AND REGISTRAR
BY
                                                           AUTHORIZED SIGNATURE

                                PEGASYSTEMS INC.

     The Corporation is authorized to issue more than one class of stock. Upon
written request, made by the holder of this Certificate, the Corporation will
furnish to such holder without charge a copy of the full text of the 
preferences, voting powers, qualifications and special and relative rights of
the shares of each class authorized to be issued, as set forth in the Restated
Articles of Organization and the votes of the Board of Directors.

     The following abbreviations, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

     TEN COM--as tenants in common
     TEN ENT--as tenants by the entireties
     JT TEN --as joint tenants with right of
              survivorship and not as tenants
              in common
     UNIF GIFT MIN ACT--________ Custodian ________
                         (Cust)             (Minor)
                        under Uniform Gifts to Minors
                        Act _______________________
                                    (State)
     UNIF TRF MIN ACT--_________ Custodian (until age ______)
                         (Cust)
                       _________ under Uniform Transfers
                        (Minor)
                       to Minors Act ______________________
                                            (State)

    Additional abbreviations may also be used though not in the above list.

    FOR VALUE RECEIVED, _________________________________________ hereby sell,
assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE
______________________________________

______________________________________


_______________________________________________________________________________
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

_______________________________________________________________________________

_______________________________________________________________________________

________________________________________________________________________ Shares
of the capital stock represented by the within Certificate, and do hereby
irrevocably constitute and appoint

______________________________________________________________________ Attorney
to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.

Dated __________________________________


X ______________________________________

X ______________________________________

NOTICE:

THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME(S) AS WRITTEN
UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR 
ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed:

By ________________________________________________________

THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION 
(BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH 
MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO 
S.E.C. RULE 17Ad-15.