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                                                                   EXHIBIT 10.51


                     VASCO Data Security International, Inc.
                   INDEPENDENT CONTRACTOR EMPLOYMENT AGREEMENT

This Employment Agreement ("Agreement"), is made and entered into as of November
20, 2002 (the "Effective Date"), by and between VASCO Data Security
International, Inc., a Delaware corporation (the "Company"), and E-SECUVISION
BVBA (incorporated on 17.11.1999), having its registered office at 8501
Bissegem, Dumortierlaan 9, hereby represented by Mr. Jan VALCKE, Managing
Director, who, as an Independent Contractor, commits himself jointly and
severally; hereinafter referred to as (the "Executive").

     WHEREAS, the Company and the Executive desire to enter into this Agreement
to establish the rights and obligations of the Executive and the Company in such
Employment relationship; and

     WHEREAS, the terms of this Agreement have been approved by the Board of
Directors of the Company,

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Executive and the Company
hereby agree as follows:

1. Employment of Executive.

     As of the Effective Date, the Company hereby engages and employs Executive
in an executive capacity as described in Exhibit A attached hereto, and
Executive hereby accepts such Employment and agrees to act as an independent
contractor to the Company in accordance with the terms of Employment hereinafter
specified ("Executive Employment").

2. Term of Executive Employment.

     The period of Executive Employment shall begin on the Effective Date and
continue until terminated as hereinafter provided (the "Employment Period").

3. Duties.

     (a) Executive shall be employed by Company as an Officer of the Company in
the capacity and with the duties set forth in Exhibit A attached hereto.

     (b) Nothing contained herein shall be construed so as to prohibit Executive
from performing such other or additional duties or responsibilities, and
exercising such other or additional authority in furtherance of the goals of the
Company, as the Executive and Chief Executive Officer and/or the Board of
Directors of the Company shall from time to time agree upon.

     (c) Executive shall devote such portion of his business time and attention
as is necessary to appropriately and efficiently discharge his duties and
responsibilities as herein set forth. If Executive so discharges his duties, he
may engage in other non-competing business and civic activities, in addition to
those relating to the Company's business, if such activities are not otherwise
prohibited by the terms of this Agreement, or do not substantially interfere
with the performance of such responsibilities.

4. Base Pay. During the Employment Period, the Company shall pay or cause to be
paid to Executive an initial base Pay ("Base Pay") as set forth in Exhibit A
attached hereto and made a part hereof, payable to Executive on a periodic basis
in accordance with the Company's then current executive payment practice;
provided, however, that the installments may not be made less frequently than on
a monthly basis. Such Base Pay shall be subject to review in accordance with the
Company's normal practice for executive Pay review from time to time in effect,
and will not be reduced without the prior written consent of Executive. Any
increase in Base Pay shall be in writing and be attached to this Agreement as an
amendment to Exhibit A.

5. Expenses. The Company shall pay or reimburse Executive in accordance with the
Company's policy for all expenses reasonably incurred by Executive during the
period of Executive's Employment in connection with the performance of
Executive's duties under this Agreement, including, without limitation, travel,
entertainment and other business related expenses. The Company will also pay to
Executive a car allowance, in lieu of reimbursing Executive for car-related
expenses,


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of 868 Euro monthly. As the Company may reasonably request, Executive shall
provide to the Company documentation or supporting information relating to the
expenses for which Executive seeks reimbursement.

6. Termination of Executive Employment Either Party shall have the option to
terminate Executive's Employment with or without cause, for any reason
whatsoever, without any breach of this Agreement by giving six (6) month's
written notice.

7. Non-Compete. In the event Executive terminates his Employment or is
terminated pursuant to this Agreement, Executive hereby agrees that he shall
not, directly or indirectly, as employee, agent, consultant, stockholder,
director, co-partner or in any other individual or representative capacity, own,
operate, manage, control, invest in or participate in any manner in, act as a
consultant or advisor to, render services for (alone or in association with any
person, firm, corporation or entity), or otherwise assist any firm, corporation
or entity which is in direct competition with the Company ("Competitor") for the
term of six (6) months provided, however, that nothing contained herein shall be
construed to prevent Executive from investing in the stock of a Competitor, but
only if Executive is not involved in the business of said Competitor and if
Executive and his associates (as such term is defined in Regulation 14(A)
promulgated under the Securities Exchange Act of 1934, as in effect on the date
hereof), collectively, do not own more than an aggregate of two (2%) percent of
the stock of such Competitor. Executive also agrees that for a period of twelve
(12) months from his termination of employment that he will not solicit any
clients of the Company, nor will he solicit for employment any Company
employees.

8. Miscellaneous.

     (a) Notice. Any notice or other communication required or permitted
hereunder shall be in writing and shall be deemed given when delivered in person
or other forms of delivery, including certified mail, fax, etc., to the
following addresses:

               (i)  if to the Company, to:

                    VASCO Data Security International, Inc.
                    1901 South Meyers Road, Suite 210
                    Oakbrook Terrace, IL 60181
                    Attn: Compensation Committee Chairman
                    with a copy to:

                    Forrest D. Laidley, Esq
                    339 N. Milwaukee Ave.
                    Suite 200
                    Libertyville, Illinois 60048

               (ii) If to Executive to:

                    To the address set forth in Exhibit A.

          Any party may change its address for notice hereunder by notice to the
other party hereto.

     (b) Governing Law. The parties agree that this Agreement shall be construed
and governed in accordance with the laws of the State of Illinois, USA,
applicable to agreements made and to be performed entirely within such state.

     (c) Binding Effect. This Agreement shall be binding upon and incur to the
benefit of the parties hereto and their respective heirs, legal representatives,
executors, administrators, successors and assigns.

     (d) Counterparts. This Agreement may be executed simultaneously in one or
more counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

     (e) Entire Agreement. This Agreement represents the entire agreement and
understanding of the parties hereto with respect to the matters set forth
herein. This Agreement supersedes all prior negotiations, discussions
correspondence, communications, understandings and agreements between the
parties, including all subsidiaries of the Company, written or oral, relating to
the subject matter of this Agreement. This specifically includes the Agreement
signed between the Executive and VASCO Data Security NV, a wholly owned
subsidiary of VASCO Data Security Europe which, in turn, is a wholly owned
subsidiary of the Parent Company, VASCO Data Security International, Inc.,
effective November 1, 1999, which is hereby



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rendered null and void. This Agreement may be amended, superseded, canceled,
renewed, or extended and the terms hereof may be waived, only by a written
instrument signed by the parties hereto or, in the case of a waiver, by the
party waiving compliance.

     (f) Waivers. No delay on the part of any party in exercising any right,
power or privilege hereunder shall operate as a waiver thereof. Nor shall any
waiver on the part of any party of any such right, power or privilege hereunder,
nor any single or partial exercise of any right, power or privilege hereunder,
preclude any other or further exercise thereof or the exercise of any other
right, power or privilege hereunder.

     (g) Arbitration. Except for any claim or dispute which gives rise or could
give rise to equitable relief under this Agreement, at the request of the
Executive any disagreement, dispute, controversy or claim arising out of or
relating to this Agreement or the breach hereof shall be settled exclusively and
finally by arbitration. The arbitration shall be conducted in accordance with
such rules and before such arbitrator as the parties shall agree and if they
fail to so agree within 15 days after demand for arbitration, such arbitration
shall be conducted in accordance with the Commercial Arbitration Rules of the
American Arbitration Association (hereinafter referred to as "AAA Rules"). Such
arbitration shall be conducted in Chicago, Illinois, or in such other city as
the parties to the dispute may designate by mutual consent. The arbitral
tribunal shall consist of three arbitrators (or such lesser number as may be
agreed upon by the parties) selected according to the procedure set forth in the
AAA Rules in effect on the date hereof and the arbitrators shall be empowered to
order any remedy which is appropriate to the proceedings and issues presented to
them. The chairman of the arbitral tribunal shall be appointed by the American
Arbitration Association from among the three arbitrators so selected. Any party
to a decision rendered in such arbitration proceedings may seek an order
enforcing the same by any court having jurisdiction.

     (h) No Strict Construction. The language used in this Agreement will be
deemed to be the language chosen by the Executive and the Company to express
their mutual intent, and no rule of strict construction will be applied against
the Executive or Company.

     IN WITNESS WHEREOF, the Company and Executive have signed this Agreement as
of the day and year written above.

                                         VASCO Data Security International, Inc.


                                         By:
                                            -----------------------------
                                                  T. Kendall Hunt
                                                  Its: CEO



                                         By:-----------------------------
                                                  Jan Valcke
                                                  Managing Director
                                                  E-SECUVISION BVBA


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                     VASCO Data Security International, Inc.
                   INDEPENDENT CONTRACTOR EMPLOYMENT AGREEMENT

                                    EXHIBIT A


Address: Jan Valcke
                  Managing Director
                  E-SECUVISION BVBA
                  8501 Bissegem, Dumortierlaan 9
                  Belgium

ANNUALIZED COMPENSATION:   260,000 EURO
                  Executive will invoice 14,576.13 Euros to VASCO Data Security
                  NV and $6,807.00 USD to VASCO Data Security, Inc. There will
                  be no adjustments as a result of changes in the Euro to U. S.
                  Dollar exchange rate.

EFFECTIVE:  NOVEMBER 20, 2002

Title:            President and Chief Operating Officer

         Duties: Executive shall act as President and Chief Operating Officer of
         the Company and shall report directly to the Company's Chief Executive
         Officer. His responsibilities shall include overseeing and managing the
         day-to-day operations of the Company including sales, marketing, R&D,
         manufacturing, human resources, shipping, and all other operations,
         with the exception of finance and administration which reports to the
         Company's Chief Financial Officer. Executive will follow the rules set
         out by the Sarbanes-Oxley Act of 2002, and will manage the Company in
         an honest and trustworthy manner. Executive will also be charged with
         communicating clearly and truthfully with investors, analysts, the
         press, and other individuals and institutions.








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