PROMISSORY NOTE
                                 ---------------


$620,000.00                                               Boston, Massachusetts
                                                          December 16, 1993

         FOR VALUE RECEIVED, the undersigned Pegasystems Inc., a Massachusetts
corporation (the "Borrower") hereby promises to pay to the order of FLEET BANK
OF MASSACHUSETTS, N.A. (the "Bank") the principal amount of Six Hundred Twenty
Thousand and 00/100 ($620,000.00) Dollars ("Principal"), with interest, at the
rate hereinafter set forth, on the daily balance of all unpaid Principal, from
the date hereof until payment in full of all Principal and interest hereunder.
As used herein, "Letter Agreement" means that certain letter agreement dated
December 16, 1993 between the Borrower and the Bank, as amended.

         Interest on all unpaid Principal shall be due and payable monthly in
arrears, on the first day of each month commencing on the first such date after
the advance of any Principal and continuing on the first day of each month
thereafter and on the date of payment of this note in full, at fluctuating rate
per annum (computed on the basis of a year of three hundred sixty (360) days for
the actual number of days elapsed) which shall at all times be equal to the sum
of (i) one-half of one (0.5%) percent per annum plus (ii) the Prime Rate, as in
effect from time to time (but in no event in excess of the maximum rate
permitted by then applicable law). A change in the aforesaid rate of interest
will become effective on the same day on which any change in the Prime Rate is
effective. Overdue Principal and, to the extent permitted by law, overdue
interest shall bear interest at a fluctuating rate per annum which at all times
shall be equal to the sum of (i) two (2%) percent per annum plus (ii) the per
annum rate otherwise payable under this note (but in no event in excess of the
maximum rate permitted by then applicable law), compounded monthly and payable
on demand. As used herein, "Prime Rate" means that rate of interest per annum
announced by the Bank from time to time as its prime rate, it being understood
that such rate is merely a reference rate, not necessarily the lowest, which
serves as the basis upon which effective rates of interest are calculated for
obligations making reference thereto.

         Principal shall be repaid in thirty-five (35) equal consecutive monthly
installments (each in an amount equal to $17,222.22) commencing on January 1,
1994 and continuing on the first day of each month thereafter through and
including November 1, 1996 plus a thirty-sixty (36th) and final payment due on
December 1, 1996 in an amount equal to all then remaining Principal and all
interest accrued but unpaid thereon. The Borrower may at any time and from time
to time, without premium or penalty, prepay all or any portion of said
Principal, each such prepayment to be applied against Principal installments in
inverse order of normal maturity.






         Payments of both Principal and interest shall be made, in immediately
available funds, at the principal office of the Bank (now located at 75 State
Street, Boston, Massachusetts 02109), or at such other address as the Bank may
from time to time designate.

         The undersigned Borrower irrevocably authorizes the Bank to make or
cause to be made, on a schedule attached to this note or on the books of the
Bank, at or following the time of making the Term Loan (as defined in the Letter
Agreement) evidenced by this note and of receiving any payment of Principal, an
appropriate notation reflecting such transaction and the then aggregate unpaid
balance of Principal. Failure of the Bank to make any such notation shall not,
however, affect any obligation of the Borrower hereunder or under the Letter
Agreement. The aggregate unpaid principal amount of the Term Loan evidenced by
this note, as recorded by the Bank from time to time on such schedule or on such
books, shall constitute prima facie evidence of such amount.

         The Borrower hereby (a) waives notice of and consents to any and all
advances, settlements, compromises, favors and indulgences (including, without
limitation, any extension or postponement of the time for payment), any and all
receipts, substitutions, additions, exchanges and releases of collateral, and
any and all additions, substitutions and releases of any person primarily or
secondarily liable, (b) waives presentment, demand, notice, protest and all
other demands and notices generally in connection with the delivery, acceptance,
performance, default or enforcement of or under this note, and (c) agrees to pay
all costs and expenses, including, without limitation, reasonable attorneys'
fees, incurred or paid by the Bank in enforcing this note and any collateral or
security therefor, all whether or not litigation is commenced.

         This note is one of the Term Notes referred to in, and is secured by
and entitled to the benefits of, the Letter Agreement. This note is subject to
prepayment as set forth in the Letter Agreement. The maturity of this note may
be accelerated upon the occurrence of an Event of Default, as provided in the
Letter Agreement.


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         Executed, as an instrument under seal, as of the day and year first
above written.


CORPORATE
  SEAL
ATTEST:
                                                 PEGASYSTEMS, INC.


- ------------------------------                   By: [Signature of Ira Vishner]
Clerk                                                 -------------------------
                                                      Its Treasurer





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