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                                                                   Exhibit 10.16


                                PROMISSORY NOTE

$300,000                                                   SAN MATEO, CALIFORNIA
                                                                FEBRUARY 7, 2002


        1. Loan. For value received, William C. Park ("BORROWER") hereby
promises to pay to the order of Digital Impact, Inc., a Delaware corporation,
and its successors and assigns ("LENDER"), in lawful money of the United States
of America, equity securities of Lender or a combination of the two, the
principal balance of THREE HUNDRED THOUSAND DOLLARS ($300,000), together with
accrued and unpaid interest thereon at the rate set forth below, on February 1,
2005.

        2. Interest. The unpaid principal amount of this Promissory Note shall
bear interest at a rate per annum equal to 2.74% calculated on the basis of a
365-day year and the actual number of days elapsed. Interest will be compounded
annually on February 1 of each year during the term of this Promissory Note.

        3. Prepayment. This Promissory Note may be prepaid in whole or in part
at any time, without premium or penalty. If at any time prior to the repayment
of all unpaid principal and interest hereunder, Borrower sells any shares of
Lender stock, Borrower shall apply fifty percent (50%) of the after-tax proceeds
of any such sale to the repayment of unpaid principal and interest hereunder. In
addition, if Borrower becomes entitled to any cash bonuses or severance payments
from Lender at any time prior to the repayment of all unpaid principal and
interest hereunder, Lender, in its discretion, may apply any portion or all of
such bonus or other payment to the repayment of unpaid principal and interest
hereunder.

        4. Termination of Employment. If Lender terminates Borrower's service
for Cause (as defined on Schedule A) or Borrower resigns other than for Good
Reason (as defined on Schedule A), all unpaid principal and interest hereunder
shall become immediately due and payable.

        5. Waiver. Borrower hereby waives presentment, demand, notice of
dishonor, protest, notice of protest and all other demands, protests and notices
in connection with the execution, delivery, performance, collection and
enforcement of this Promissory Note. Borrower shall pay all costs of collection
when incurred, including reasonable attorneys' fees, costs and expenses.

        6. Miscellaneous. This Promissory Note may only be amended, modified or
terminated by an agreement in writing signed by the party to be charged. This
Promissory Note shall be binding upon the heirs, executors, administrators,
successors and assigns of Borrower and inure to the benefit of Lender and its
permitted successors, endorsees and assigns. This Promissory Note shall not be
transferred without the express written consent of Lender, provided that if
Lender consents to any such transfer or if notwithstanding the foregoing such a
transfer occurs, then the provisions of this Promissory Note shall be binding
upon any successor to Borrower and shall inure to the benefit of and be extended
to any holder thereof. This Promissory Note is being delivered in, is intended
to be


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performed in, shall be construed and interpreted in accordance with, and be
governed by the internal laws of, the State of California, without regard to
principles of conflict of laws.

        BORROWER UNDERSTANDS THAT THIS IS A FULL RECOURSE PROMISSORY NOTE AND
THAT LENDER MAY, AT ITS OPTION, PROCEED AGAINST ANY OF THE ASSETS OF BORROWER IN
THE EVENT OF A DEFAULT.

                                             WILLIAM C. PARK

                                             ________________________________






                                       2

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                                   SCHEDULE A

        "CAUSE" shall mean the willful engaging by Borrower in criminal or
fraudulent acts or gross misconduct that is demonstrably and materially
injurious to Lender, monetarily or otherwise. No act or failure to act on
Borrower's part shall be deemed "willful" unless done or omitted to be done by
Borrower not in good faith and without reasonable belief that Borrower's action
or omission was in the best interest of Lender. Notwithstanding the foregoing,
Borrower shall not be deemed to have been terminated for Cause unless and until
there shall have been delivered to Borrower a copy of a resolution duly adopted
by the affirmative vote of not less than three quarters (3/4) of the
non-employee members of the Board at a meeting of the Board called and held for
such purpose (after reasonable notice to Borrower and an opportunity for
Borrower, together with Borrower's counsel, to be heard before the Board),
finding that in the good faith opinion of the Board, Borrower was guilty of
conduct set forth above in the first sentence of this definition and specifying
the particulars thereof in detail.

        "GOOD REASON" shall mean, without Borrower's express written consent,
(i) a material and detrimental alteration of Borrower's responsibilities from
those in effect on the date hereof or (ii) the relocation of the office of
Lender where Borrower is employed on the date hereof to a location which is more
than 35 miles away from such office or Lender's requiring Borrower to be based
more than 35 miles away from such office (except for required travel on Lender's
business to an extent substantially consistent with Borrower's customary
business travel obligations in the ordinary course of business prior to the date
hereof).