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                                                               EXHIBIT 10.10
                                 PROMISSORY NOTE

$1,478,832.38                                                    March 15, 2002
                                                               Atlanta, Georgia

         FOR VALUE RECEIVED, the undersigned, DAVID GOULD ("Borrower"), promises
to pay to the order of WITNESS SYSTEMS, INC., a Delaware corporation (the
"Lender"), in lawful money of the United States of America constituting legal
tender in payment of all debts and dues, public and private, the principal
amount of One Million Four Hundred Seventy Eight Thousand Eight Hundred Thirty
Two and 38/100 Dollars ($1,478,832.38).

         1.       INTEREST. From and after the date hereof (until maturity or
default as hereinafter provided), interest on the principal amount outstanding
shall accrue at an adjustable rate per annum equal to 325 basis points (3.25%)
in excess of the Federal Funds Rate (as hereinafter defined), and computed on
the basis of a 365-day year. The interest rate shall be adjusted monthly on the
first day of each calendar month hereafter upon any change in the Federal Funds
Rate to the appropriate percentage above the Federal Funds Rate most recently in
effect. "Federal Funds Rate" shall mean the rate per annum (rounded upwards, if
necessary, to the next 1/100th of 1%) equal to the weighted average of the rates
on overnight Federal funds transactions with member banks of the Federal Reserve
System arranged by Federal funds brokers, as published by the Federal Reserve
Bank of New York on the next succeeding business day.

         2.       PAYMENT.

                  (a)   Interest on the outstanding principal balance of the
                        indebtedness evidenced hereby shall be payable annually
                        with the initial payment due on or before February 1,
                        2003.

                  (b)   One third (1/3) of the principal balance of the
                        indebtedness evidenced hereby shall be due and payable
                        on or before each of the following dates:

                           (i)      February 1, 2003;
                           (ii)     February 1, 2004; and
                           (iii)    February 1, 2005.

                  (c)   On February 1, 2005 (the "Maturity Date"), the entire
                        outstanding principal balance of the indebtedness
                        evidenced hereby plus all accrued but unpaid interest
                        thereon shall be due and payable in full.

                  (d)   Notwithstanding anything herein to the contrary, the
                        entire outstanding principal balance of the
                        indebtedness evidenced hereby and all accrued but
                        unpaid interest shall be due and payable in full upon
                        the first to occur of the following:

                           (i)      The Maturity Date; or

                           (ii)     Ninety (90) days following the effective
                                    date of termination of Borrower's full time
                                    employment with the Lender, unless otherwise
                                    agreed to by Lender and Borrower.

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         3.       PREPAYMENT.

This Note may be prepaid in whole or in part without penalty, provided that any
partial prepayment shall be in integral multiples of $1,000.00.

         4.       SECURITY.

                  a.    Maintenance of Collateral. On the date hereof, Maker has
                        pledged to Lender, as collateral security, collateral of
                        a type described in the stock pledge agreement of even
                        date herewith, with a Collateral Value (as determined
                        herein) equal to at least 2.5 times the balance of this
                        Note. If at any time while this Note is outstanding, the
                        Collateral Value (as determined herein) of the
                        collateral shall be less than 1.5 times the unpaid
                        principal balance of this Note, Maker shall immediately
                        comply with Section 4b, below. The "Collateral Value" of
                        collateral shall be determined at any given time by
                        multiplying (i) the per share price of such stock at the
                        most recent close of trading on a trading exchange for
                        such stock (the "Market Value"), times (ii) the number
                        of shares of such stock held by Lender as collateral.
                        For all purposes the value of a share of Witness stock
                        shall be the Market Value.

                  b.    Breach of Collateral Maintenance. Maker agrees that the
                        failure to maintain collateral with a Collateral Value
                        as set forth above shall constitute an Event of Default
                        under this Note. In such event, the Maker shall, within
                        ten business days after the date Maker is notified by
                        Lender (in writing or orally) of such noncompliance,
                        either pledge additional collateral satisfactory to
                        Lender, in its sole discretion, or reduce the unpaid
                        principal balance of this Note such that, in either
                        case, the Collateral Value is then equal to at least 2.5
                        times the unpaid principal balance of this Note. Failure
                        to achieve the foregoing within ten business days after
                        the giving of notice by Lender as aforesaid shall be an
                        Event of Default under this Note. Notwithstanding the
                        foregoing terms of this Section 4.b., in the event that
                        during such ten business day period the Collateral Value
                        is equal to 1.1 or less times the principal balance of
                        the Note, then there shall immediately be an Event of
                        Default.

                  c.    Sale or Substitution of Collateral. If no Event of
                        Default has occurred under this Note or would result
                        from such action, Maker may sell, trade, or withdraw any
                        part of the collateral; provided that the Collateral
                        Value shall continue to equal at least 2.5 times the
                        unpaid principal balance of this Note.

         5.       DEFAULT.

                  a.    Event of Default. An event of default ("Event of
                        Default") shall occur (a) if Maker or any other obligor
                        on all or part of this Note shall fail to timely and
                        properly pay or observe, keep or perform any term,
                        covenant, agreement or condition in this Note or in any
                        other agreement between Maker and Lender or between
                        Lender and any other obligor on this Note.

                  b.    Rights and Remedies. If any Event of Default shall
                        occur, then, in each and every such case, Lender may,
                        without (a) presentment, demand, or protest, (b) notice
                        of default, dishonor, demand, non-payment, or protest,
                        (c) notice of intent to accelerate all or any part of
                        the obligation represented hereby, (d) notice of
                        acceleration of all or any part of the obligation
                        represented hereby, or (e) notice of any other kind, all
                        of which Maker hereby expressly waives (except for any
                        notice required under this Note,

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             any other loan document or which may not be waived under applicable
             law), at any time thereafter exercise and/or enforce any of the
             following rights and remedies, at Lender's option:


                  i.       Acceleration. The obligation represented hereby
                           shall, at Lender's option, become immediately due and
                           payable, and the obligation, if any, of Lender to
                           permit further borrowings shall at Lender's option
                           immediately cease and terminate.

                  ii.      Retirement of Collateral. Instruct any Agent or
                           Broker to release, all or any part of the collateral
                           to Lender, retire such collateral, and apply an
                           amount equal to the Market Value per share to the
                           payment of any or all of the obligation represented
                           hereby in such order and manner as Lender shall, in
                           its discretion, choose.

                  iii.     Uniform Commercial Code. All of the rights, powers
                           and remedies of a secured creditor under the Uniform
                           Commercial Code ("UCC") as adopted in the
                           jurisdiction to which Lender is subject under this
                           Agreement.

         Maker specifically understands and agrees that any sale by Lender of
all or part of the collateral pursuant to the terms of this Agreement may be
effected by Lender at times and in manners which could result in the proceeds of
such sale being significantly and materially less than might have been received
if such sale had occurred at different times or in different manners, and Maker
hereby releases Lender and its officers and representatives from and against any
and all obligations and liabilities arising out of or related to the timing or
manner of any such sale.

         If, in the opinion of Lender, there is any question that a public sale
or distribution of any collateral will violate any state or federal securities
law, Lender may offer and sell such Collateral in a transaction exempt from
registration under federal securities law, and any such sale made in good faith
by Lender shall be deemed "commercially reasonable."

         Notwithstanding anything to the contrary in this Note, the Maker shall
have the right, on and after the date which is six months plus one day after the
date of this Note, to meet Maker's collateral maintenance obligations under
Section 4 of this Note by directing Lender to recover and retire a number of
shares held under the pledge agreement, and apply the fair market value thereof
to reduce the balance due under this Note, such that the collateral maintenance
requirements of Section 4 hereof are thereby satisfied. If, prior to such date,
an Event of Default shall occur under this Note, the rate of interest payable on
the unpaid principal balance hereunder shall thereafter equal 18% per annum.

         6.       RECOURSE. Borrower shall be 100% personally liable for the
obligations evidenced hereby.

         7.       PAYMENT IN SHARES. Subsequent to the date which is six (6)
months after the date of this Note, Borrower may make any payment due and
payable or otherwise permitted hereunder by delivery of shares of Lender's
common stock owned by and fully vested in Borrower to Lender; provided, however,
that any such shares delivered as payment hereunder shall have been owned by,
vested in and fully paid for by Borrower for more than six (6) months prior to
the date such payment is made. For purposes of payments hereunder, any shares of
Lender's common stock shall be valued at their then fair market value

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(as determined by the closing market price on NASDAQ on the date of tender) for
application to the balance of the principal and all interest payments hereunder.

         8.       WAIVERS. Borrower hereby waives demand, presentment for
payment, notice of dishonor, protest, and notice of protest and diligence in
collection or bringing suit and agree that the holder hereof may accept partial
payment, or release or exchange security or collateral, without discharging or
releasing any unreleased collateral or the obligations evidenced hereby.
Borrower further waives any and all rights of exemption, both as to personal and
real property, under the constitution or laws of the United States or the State
of Georgia.

         9.       ATTORNEYS' FEES. Borrower agrees to pay reasonable attorneys'
fees and costs actually incurred by the holder hereof in collecting on this
Note, whether by suit or otherwise.

         10.      UNCONDITIONAL PAYMENT. Borrower is and shall be obligated to
pay principal and any and all other amounts which become payable hereunder
absolutely and unconditionally and without any abatement, postponement,
diminution or deduction and without any reduction for counterclaim or setoff. In
the event that at any time any payment received by Lender hereunder shall be
deemed by a court of competent jurisdiction to have been a voidable preference
or fraudulent conveyance under any bankruptcy, insolvency or other debtor relief
law, then the obligation to make such payment shall survive any cancellation or
satisfaction of this Note or return thereof to Borrower and shall not be
discharged or satisfied with any prior payment thereof or cancellation of this
Note, but shall remain a valid and binding obligation enforceable in accordance
with the terms and provisions hereof, and such payment shall be immediately due
and payable upon demand.

         11.      MISCELLANEOUS. As used herein, the terms "Borrower," "Lender"
and "holder" shall be deemed to include their respective successors, legal
representatives and assigns, whether by voluntary action of the parties or by
operation of law. This Note is given under the seal of the Borrower, and it is
intended that this Note is and shall constitute and have the effect of a sealed
instrument according to law. This Note has been negotiated, and is being
executed and delivered in the State of Georgia, or if executed elsewhere, shall
become effective upon the Lender's receipt and acceptance of the executed
original of this Note in the State of Georgia; provided, however, that the
Lender shall have no obligation to give, nor shall Borrower be entitled to
receive, any notice of such acceptance for this Note to become a binding
obligation of Borrower. Borrower hereby submits to jurisdiction in the State of
Georgia. This Note shall be governed by and be construed in accordance with the
laws of the State of Georgia. It is intended, and the Borrower and the holder
hereof specifically agree, that the laws of the State of Georgia governing
interest shall apply to this Note and to this transaction. This Note may not be
modified except by written agreement signed by the Borrower and the holder
hereof, or by their respective successors or assigns.

         12.      TIME OF ESSENCE.TIME IS OF THE ESSENCE in connection with this
Note.

         IN WITNESS WHEREOF, Borrower has caused this Note to be executed and
delivered under seal as of the date first set forth above.

LENDER:                                                       BORROWER:

/s/ Loren Wimpfheimer                              /s/ David Gould        [SEAL]
---------------------                              -----------------------
By: Loren Wimpfheimer, SVP                         David Gould
Witness Systems, Inc