Exhibit 10.16

BANK OF AMERICA

                                Promissory Note

Date: November 22, 2000           New Obligor #

Amount: $3,000,000.00            Maturity Date: November 22, 2001

 Bank:                               Borrower:
 Bank of America, N.A.               Omega Research, Inc.
 Banking Center: Private Bank        8700 West Flagler Street, Suite 250
 100 S.E. 2nd Street, 47th Floor     Miami, Florida 33174
 Miami, Florida 33131
 County: Miami-Dade, Florida         County: Miami-Dade, Florida

FOR VALUE RECEIVED, the undersigned Borrower unconditionally (and jointly and
severally, if more than one) promises to pay to the order of Bank, its
successors and assigns, without setoff, at its offices indicated at the
beginning of this Note, or at such other place as may be designated by Bank,
the principal amount of Three Million and 00/100 Dollars ($3,000,000.00), or so
much thereof as may be advanced in immediately available funds, together with
interest computed daily on the outstanding principal balance hereunder, at an
annual interest rate, and in accordance with the payment schedule, indicated
below.

[This Note contains some provisions preceded by boxes. If a box is marked, the
provision applies to this transaction; if it is not marked, the provision does
not apply to this transaction.]

1. Rate.

The Rate shall be the Eurodollar Rate, plus 1.70%, per annum. The "Eurodollar
Rate" is a fluctuating rate of interest equal to the one month rate of interest
(rounded upwards, if necessary to the nearest 1/100 of 1%) appearing on
Telerate Page 3750 (or any successor page) as the one month London interbank
offered rate for deposits in Dollars at approximately 11:00 a.m. (London time)
on the second preceding business day, as adjusted from time to time in Bank's
sole discretion for then-applicable reserve requirements, deposit insurance
assessment rates and other regulatory costs. If for any reason such rate is not
available, the term "Eurodollar Rate" shall mean the fluctuating rate of
interest equal to the one month rate of interest (rounded upwards, if necessary
to the nearest 1/100 of 1%) appearing on Reuters Screen LIBO Page as the one
month London interbank offered rate for deposits in Dollars at approximately
11:00 a.m. (London time) on the second preceding business day, as adjusted from
time to time in Bank's sole discretion for then-applicable reserve
requirements, deposit insurance assessment rates and other regulatory costs;
provided, however, if more than one rate is specified on Reuters Screen LIBO
Page, the applicable rate shall be the arithmetic mean of all such rates.

Notwithstanding any provision of this Note, Bank does not intend to charge and
Borrower shall not be required to pay any amount of interest or other charges
in excess of the maximum permitted by

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the applicable law of the State of Florida; if any higher rate ceiling is
lawful, then that higher rate ceiling shall apply. Any payment in excess of
such maximum shall be refunded to Borrower or credited against principal, at
the option of Bank.

2. Accrual Method. Unless otherwise indicated, interest at the Rate set forth
above will be calculated by the actual/360 day method (a daily amount of
interest is computed for a hypothetical year of 360 days; that amount is
multiplied by the actual number of days for which any principal is outstanding
hereunder). If interest is not to be computed using this method, the method
shall be: N/A.

3. Rate Change Date. Any Rate based on a fluctuating index or base rate will
change, unless otherwise provided, each time and as of the date that the index
or base rate changes. If the Rate is to change on any other date or at any
other interval, the change shall be: N/A.

In the event any index is discontinued, Bank shall substitute an index
determined by Bank to be comparable, in its sole discretion.

4. Payment Schedule. All payments received hereunder shall be applied first to
the payment of any expense or charges payable hereunder or under any other loan
documents executed in connection with this Note, then to interest due and
payable, with the balance applied to principal, or in such other order as Bank
shall determine at its option.

     Single Principal Payment. Principal shall be paid in full in a single
payment on November   , 2001. Interest thereon shall be paid monthly,
commencing on November 30, 2000, and continuing on the last day of each
successive month thereafter, with a final payment of all unpaid interest at the
stated maturity of this Note.

5. Revolving Feature.

[X] Borrower may borrow, repay and reborrow hereunder at any time, up to a
maximum aggregate amount outstanding at any one time equal to the principal
amount of this Note, provided, that Borrower is not in default under any
provision of this Note, any other documents executed in connection with this
Note, or any other note or other loan documents now or hereafter executed in
connection with any other obligation of Borrower to Bank, and provided that the
borrowings hereunder do not exceed any borrowing base or other limitation on
borrowings by Borrower. Bank shall incur no liability for its refusal to
advance funds based upon its determination that any conditions of such further
advances have not been met. Bank records of the amounts borrowed from time to
time shall be conclusive proof thereof.

     [ ] Uncommitted Facility. Borrower acknowledges and agrees that,
notwithstanding any provisions of this Note or any other documents executed in
connection with this Note, Bank has no obligation to make any advance, and that
all advances are at the sole discretion of Bank.

     [ ] Out-Of-Debt Period. For a period of at least     consecutive days
during [ ] each fiscal year, [ ] any consecutive 12-month period, Borrower
shall fully pay down the balance of this Note, so that no amount of principal
or interest and no other obligation under this Note remains outstanding.

Borrower will pay hereafter on November 30, 2000 and on the last day of each
month for the period from and including the closing date, to and including the
maturity date of the Note an unused facility fee at a rate per annum of 0.125
(0.125%) of the average daily unused portion of the Note during such period in
the maximum aggregate amount of Three Million Dollars ($3,000,000.00). The
Borrower may at any time upon written notice to the Bank reduce the amount of
the Line at which time the obligation of the Borrower to pay a commitment fee
shall thereupon correspondingly be reduced. On the date hereof, Borrower will
pay to the Bank a commitment fee of $7,500.00 (.25% of Three Million Dollars).

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6. Automatic Payment.

Borrower authorizes Bank to effect payment of sums due under this Note by means
of debiting Borrower's account number            . This authorization shall not
affect the obligation of Borrower to pay such sums when due, without notice, if
there are insufficient funds in such account to make such payment in full on
the due date thereof, or if Bank fails to debit the account.

7. Representation and Warranties. The Borrower requests and warrants to the
Bank that as of the date hereof: (i) the execution, delivery and performance of
Borrower of the Loan Documents does not violate either applicable law, the
articles or by-laws of the Borrower or any agreement to which Borrower is
subject; (ii) there is no litigation pending against Borrower except as
previously disclosed in writing to Bank; and (iii) there has been no material
adverse change in the final condition of the Borrower since September 30, 2000
except as otherwise disclosed on or before this date in writing to Bank by
Borrower.

8. Waivers, Consents and Covenants. Borrower, any endorser or Guarantor (as
defined hereinbelow) hereof, or any other party executing a Loan Document that
supports and/or secures payment of this Note, (individually an "Obligor" and
collectively "Obligors") and each of them jointly and severally: (a) waive
presentment, demand, protest, notice of demand, notice of intent to accelerate,
notice of acceleration of maturity, notice of protest, notice of nonpayment,
notice of dishonor, and any other notice required to be given under the law to
any Obligor in connection with the delivery, acceptance, performance, default
or enforcement of this Note, any endorsement or guaranty of this Note, or any
other documents executed in connection with this Note including but not limited
to: mortgage, deed of trust, security instrument or pledge agreement, or any
other note or other loan documents now or hereafter executed in connection with
any obligation of Borrower to Bank, including, but not limited to, the Guaranty
of even date in favor of Bank and executed by Rafael L. Cruz and Guillermo R.
Cruz (who are collectively referred to herein as "Guarantor") (all of which
documents are collectively referred to herein as the "Loan Documents"); (b)
consent to all delays, extensions, renewals or other modifications of this Note
or the Loan Documents, or waivers of any term hereof or of the Loan Documents,
or release or discharge by Bank of any of Obligors, or release, substitution or
exchange of any security for the payment hereof, or the failure to act on the
part of Bank, or any indulgence shown by Bank (without notice to or further
assent from any of Obligors), and agree that no such action, failure to act or
failure to exercise any right or remedy by Bank shall in any way affect or
impair the obligations of any Obligors or be construed as a waiver by Bank of,
or otherwise affect, any of Bank's rights under this Note, under any
endorsement or guaranty of this Note or under any of the Loan Documents; and
(c) agree to pay, on demand, all costs and expenses of collection or defense of
this Note or of any endorsement or guaranty hereof and/or the enforcement or
defense of Bank's rights with respect to, or the administration, supervision,
preservation, or protection of, or realization upon, any property securing
payment hereof, including, without limitation, reasonable attorney's and
paralegal's fees, including fees related to any suit, mediation or arbitration
proceeding, out of court payment agreement, trial, appeal, bankruptcy
proceedings or other proceeding, in such amount as may be determined reasonable
by any arbitrator or court, whichever is applicable.

9. Indemnification. Obligors agree to promptly pay, indemnify and hold Bank
harmless from all State and Federal taxes of any kind and other liabilities
with respect to or resulting from the execution and/or delivery of this Note or
any advances made pursuant to this Note. If this Note has a revolving feature
and is secured by a mortgage, Obligors expressly consent to the deduction of
any applicable taxes from each taxable advance extended by Bank.

10. Prepayments. Prepayments may be made in whole or in part at any time. All
prepayments of principal shall be applied in the inverse order of maturity, or
in such other order as Bank shall determine in its sole discretion.

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11. Delinquency Charge. To the extent permitted by law, a delinquency charge
may be imposed in an amount not to exceed four percent (4%) of any payment that
is more than fifteen days late.

12. Events of Default. The following are events of default hereunder: (a) the
failure to pay or perform any obligation, liability or indebtedness of any
Obligor to Bank, or to any affiliate or subsidiary of Bank of America
Corporation, whether under this Note or any Loan Documents, as and when due
(whether upon demand, at maturity or by acceleration); (b) a default (after
giving effect to any cure period relating to such default) arising from the
failure to pay or perform any other obligation, liability or indebtedness of
any Obligor to any other party which obligation, liability or indebtedness,
singly or in the aggregate, exceeds $200,000.00; (c) the death of any Obligor
(if an individual); (d) the resignation or withdrawal of any partner or a
material owner/guarantor of Borrower, as determined by Bank in its sole
discretion; (e) the commencement of a proceeding against any Obligor for
dissolution or liquidation, the voluntary or involuntary termination or
dissolution of any Obligor or the merger or consolidation of any Obligor with
or into another entity; (f) the insolvency of, the business failure of, the
appointment of a custodian, trustee, liquidator or receiver for or for any of
the property of, the assignment for the benefit of creditors by, or the filing
of a petition under bankruptcy, insolvency or debtor's relief law or the filing
of a petition for any adjustment of indebtedness, composition or extension by
or against any Obligor; (g) the determination by Bank that any representation
or warranty made to Bank by any Obligor in any Loan Documents or otherwise is
or was, when it was made, untrue or materially misleading; (h) the failure of
any Obligor to timely deliver such financial statements, including tax returns
and all schedules, and other statements of condition or other information, as
Bank shall reasonably request from time to time; (i) the entry of a judgment
against any Obligor which Bank reasonably deems to be of a material nature; (j)
the seizure or forfeiture of, or the issuance of any writ of possession,
garnishment or attachment, or any turnover order for any property of any
Obligor the effect of which would reasonably be expected to have a material
adverse effect on the Obligor's financial condition; (k) the reasonable
determination by Bank that a material adverse change has occurred in the
financial condition of any Obligor; or (l) the failure of Borrower's business
to comply with any law or regulation controlling its operation the effect of
which would reasonably be expected to have a material adverse effect on
Borrower's financial condition.

Notwithstanding Section 11 (d) and (e) above, no Event of Default shall be
deemed to have occurred as a result of the acquisition by TradeStation Group,
Inc. of 100% of Borrower's outstanding stock and the change of Borrower's name
to TradeStation Technologies, Inc.; provided that, Borrower complies with the
following simultaneously with or immediately after such transactions:

a. Bank shall receive evidence satisfactory to it in its sole discretion that
Borrower has not merged, consolidated or transferred all or a material portion
of its assets to any other entity as a result of such change of control (except
for mergers and consolidations where Borrower is the surviving entity);
b. Borrower shall expressly ratify and affirm in writing all of Borrower's
obligations under this Note and all other Loan Documents and executed such
amendments, modifications and replacements of the Loan Documents as the Bank
shall request in connection with the acquisition and name change;
c. Immediately after giving effect to such transactions, no default or Event of
Default shall have occurred or shall exist hereunder or under any other Loan
Document; and
d. any guarantor of Borrower's obligations hereunder shall have ratified and
confirmed that such guaranty remains in full force and effect despite such
acquisition and name change.

Borrower shall deliver, or cause to be delivered, to the Bank such
certificates, and opinions of counsel and other documents as the Bank may
request to confirm compliance with the foregoing conditions, all in form and
substance reasonably satisfactory to the Bank.

13. Remedies upon Default. Whenever there is a default under this Note (a) the
entire balance outstanding hereunder and all other obligations of any Obligor
to Bank (however acquired or evidenced) shall, at the option of Bank, become
immediately due and payable and any obligation of

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Bank to permit further borrowing under this Note shall immediately cease and
terminate, and/or (b) to the extent permitted by law, the Rate of interest on
the unpaid principal shall be increased at Bank's discretion up to the lesser
of (i) the Rate otherwise applicable hereunder plus four percent (4.00%) per
annum and (ii) the maximum rate allowed by law (the "Default Rate"). The
provisions herein for a Default Rate shall not be deemed to extend the time for
any payment hereunder or to constitute a "grace period" giving Obligors a right
to cure any default. At Bank's option, any accrued and unpaid interest, fees or
charges may, for purposes of computing and accruing interest on a daily basis
after the due date of the Note or any installment thereof, be deemed to be a
part of the principal balance, and interest shall accrue on a daily compounded
basis after such date at the Default Rate provided in this Note until the
entire outstanding balance of principal and interest is paid in full. Upon a
default under this Note, Bank is hereby authorized at any time, at its option
and without notice or demand, to set off and charge against any deposit
accounts of any Obligor (as well as any money, instruments, securities,
documents, chattel paper, credits, claims, demands, income and any other
property, rights and interests of any Obligor), which at any time shall come
into the possession or custody or under the control of Bank or any of its
agents, affiliates or correspondents, any and all obligations due hereunder.
Additionally, Bank shall have all rights and remedies available under each of
the Loan Documents, as well as all rights and remedies available at law or in
equity. Any judgment rendered on this Note shall bear interest at the highest
rate of interest permitted pursuant to Chapter 687, Florida Statutes.

14. Non-Waiver. The failure at any time of Bank to exercise any of its options
or any other rights hereunder shall not constitute a waiver thereof, nor shall
it be a bar to the exercise of any of its options or rights at a later date.
All rights and remedies of Bank shall be cumulative and may be pursued singly,
successively or together, at the option of Bank. The acceptance by Bank of any
partial payment shall not constitute a waiver of any default or of any of
Bank's rights under this Note. No waiver of any of its rights hereunder, and no
modification or amendment of this Note, shall be deemed to be made by Bank
unless the same shall be in writing, duly signed on behalf of Bank; each such
waiver shall apply only with respect to the specific instance involved, and
shall in no way impair the rights of Bank or the obligations of Obligors to
Bank in any other respect at any other time.

15. Applicable Law, Venue and Jurisdiction. This Note and the rights and
obligations of Borrower and Bank shall be governed by and interpreted in
accordance with the law of the State of Florida. In any litigation in
connection with or to enforce this Note or any endorsement or guaranty of this
Note or any Loan Documents, Obligors, and each of them, irrevocably consent to
and confer personal jurisdiction on the courts of the State of Florida or the
United States located within the State of Florida and expressly waive any
objections as to venue in any such courts. Nothing contained herein shall,
however, prevent Bank from bringing any action or exercising any rights within
any other state or jurisdiction or from obtaining personal jurisdiction by any
other means available under applicable law. The interest rate charged on this
Note is authorized by Chapter 655, Florida Statutes and Section 687.12, Florida
Statutes.

16. Partial Invalidity. The unenforceability or invalidity of any provision of
this Note shall not affect the enforceability or validity of any other
provision herein and the invalidity or unenforceability of any provision of
this Note or of the Loan Documents to any person or circumstance shall not
affect the enforceability or validity of such provision as it may apply to
other persons or circumstances.

17. Binding Effect. This Note shall be binding upon and inure to the benefit of
Borrower, Obligors and Bank and their respective successors, assigns, heirs and
personal representatives, provided, however, that no obligations of Borrower or
Obligors hereunder can be assigned without prior written consent of Bank.

18. Controlling Document. To the extent that this Note conflicts with or is in
any way incompatible with any other document related specifically to the loan
evidenced by this Note, this Note shall

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control over any other such document, and if the Note does not address an
issue, then each other such document shall control to the extent that it deals
most specifically with an issue.

19. ARBITRATION. ANY CONTROVERSY OR CLAIM BETWEEN OR AMONG THE PARTIES HERETO
INCLUDING BUT NOT LIMITED TO THOSE ARISING OUT OF OR RELATING TO THIS
INSTRUMENT, AGREEMENT OR DOCUMENT OR ANY RELATED INSTRUMENTS, AGREEMENTS OR
DOCUMENTS, INCLUDING ANY CLAIM BASED ON OR ARISING FROM AN ALLEGED TORT, SHALL
BE DETERMINED BY BINDING ARBITRATION IN ACCORDANCE WITH THE FEDERAL ARBITRATION
ACT (OR IF NOT APPLICABLE, THE APPLICABLE STATE LAW), THE RULES OF PRACTICE AND
PROCEDURE FOR THE ARBITRATION OF COMMERCIAL DISPUTES OF J.A.M.S./
ENDISPUTE OR ANY SUCCESSOR THEREOF ("J.A.M.S."), AND THE "SPECIAL RULES" SET
FORTH BELOW. IN THE EVENT OF ANY INCONSISTENCY, THE SPECIAL RULES SHALL
CONTROL. JUDGMENT UPON ANY ARBITRATION AWARD MAY BE ENTERED IN ANY COURT HAVING
JURISDICTION. ANY PARTY TO THIS INSTRUMENT, AGREEMENT OR DOCUMENT MAY BRING AN
ACTION, INCLUDING A SUMMARY OR EXPEDITED PROCEEDING, TO COMPEL ARBITRATION OF
ANY CONTROVERSY OR CLAIM TO WHICH THIS AGREEMENT APPLIES IN ANY COURT HAVING
JURISDICTION OVER SUCH ACTION.

     A. SPECIAL RULES. THE ARBITRATION SHALL BE CONDUCTED IN THE COUNTY OF ANY
BORROWER'S DOMICILE AT THE TIME OF THE EXECUTION OF THIS INSTRUMENT, AGREEMENT
OR DOCUMENT, OR IF THERE IS REAL OR PERSONAL PROPERTY COLLATERAL, IN THE COUNTY
WHERE SUCH REAL OR PERSONAL PROPERTY IS LOCATED AND ADMINISTERED BY J.A.M.S.
WHO WILL APPOINT AN ARBITRATOR; IF J.A.M.S. IS UNABLE OR LEGALLY PRECLUDED FROM
ADMINISTERING THE ARBITRATION, THEN THE AMERICAN ARBITRATION ASSOCIATION WILL
SERVE. ALL ARBITRATION HEARINGS WILL BE COMMENCED WITHIN 90 DAYS OF THE DEMAND
FOR ARBITRATION; FURTHER, THE ARBITRATOR SHALL ONLY, UPON A SHOWING OF CAUSE,
BE PERMITTED TO EXTEND THE COMMENCEMENT OF SUCH HEARING FOR UP TO AN ADDITIONAL
60 DAYS.

     B. RESERVATION OF RIGHTS. NOTHING IN THIS ARBITRATION PROVISION SHALL BE
DEEMED TO (I) LIMIT THE APPLICABILITY OF ANY OTHERWISE APPLICABLE STATUTES OF
LIMITATION OR REPOSE AND ANY WAIVERS CONTAINED IN THIS INSTRUMENT, AGREEMENT OR
DOCUMENT; OR (II) BE A WAIVER BY BANK OF THE PROTECTION AFFORDED TO IT BY 12
U.S.C. SEC. 91 OR ANY SUBSTANTIALLY EQUIVALENT STATE LAW; OR (III) LIMIT THE
RIGHT OF BANK HERETO (A) TO EXERCISE SELF HELP REMEDIES SUCH AS (BUT NOT
LIMITED TO) SETOFF, OR (B) TO FORECLOSE AGAINST ANY REAL OR PERSONAL PROPERTY
COLLATERAL, OR (C) TO OBTAIN FROM A COURT PROVISIONAL OR ANCILLARY REMEDIES
SUCH AS (BUT NOT LIMITED TO) INJUNCTIVE RELIEF, WRIT OF POSSESSION OR THE
APPOINTMENT OF A RECEIVER. BANK MAY EXERCISE SUCH SELF HELP RIGHTS, FORECLOSE
UPON SUCH PROPERTY, OR OBTAIN SUCH PROVISIONAL OR ANCILLARY REMEDIES BEFORE,
DURING OR AFTER THE PENDENCY OF ANY ARBITRATION PROCEEDING BROUGHT PURSUANT TO
THIS INSTRUMENT, AGREEMENT OR DOCUMENT. NEITHER THIS EXERCISE OF SELF HELP
REMEDIES NOR THE INSTITUTION OR MAINTENANCE OF AN ACTION FOR FORECLOSURE OR
PROVISIONAL OR ANCILLARY REMEDIES SHALL CONSTITUTE A WAIVER OF THE RIGHT OF ANY
PARTY, INCLUDING THE CLAIMANT IN ANY SUCH ACTION, TO ARBITRATE THE MERITS OF
THE CONTROVERSY OR CLAIM OCCASIONING RESORT TO SUCH REMEDIES.

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Borrower represents to Bank that the proceeds of this loan are to be used
primarily for business, commercial or agricultural purposes. Borrower
acknowledges having read and understood, and agrees to be bound by, all terms
and conditions of this Note and hereby executes this Note under seal as of the
date here above written.

NOTICE OF FINAL AGREEMENT. THIS WRITTEN PROMISSORY NOTE REPRESENTS THE FINAL
AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

If this Note is secured by a mortgage on real property, documentary stamp taxes
have been paid and affixed to the mortgage.

EXECUTION DATE: November 22, 2000

Borrower:

Omega Research, Inc.

By: /s/ Gregg F. Stewart (Seal)
   ---------------------
Name: Gregg F. Stewart
Title: CFO, V.P. Finance & Treasurer

[Corporate Seal]

     The undersigned Capt. A. Gary, Captain of the Ship Sissy Baby, hereby
certifies the execution of the foregoing by           at          , and the
immediate delivery of the foregoing to Evan Reed, as authorized representative
of Bank of America, N.A.

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