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                                                                    Exhibit 10.1

          AGREEMENT, dated as of September 11, 2002 (the "Agreement"), between
THE ASHTON TECHNOLOGY GROUP, INC., a Delaware corporation (the "Company"), and
ROBERT J. WARSHAW, an individual (the "Executive").

     Whereas the Executive has been serving as the interim Chief Executive
Officer of the Company; and

     Whereas, the Company and the Executive desire to set forth their
understanding concerning the Executive's compensation from the Company.

     Accordingly, in consideration of the premises and mutual covenants
contained herein and for other good and valuable consideration, the receipt and
adequacy of which are mutually acknowledged, the Company and the Executive agree
as follows:

          1. Service and Compensation. The Executive shall continue to serve as
interim Chief Executive Officer of the Company until December 31, 2002, or if
earlier, until the Company employs a permanent Chief Executive Officer. The
Executive shall also continue to serve as a member of the board of directors of
the Company. The Company acknowledges that the Executive will be employed
simultaneously as Chief Executive Officer of Optimark Holdings, Inc. and its
subsidiary, Optimark, Inc., and will serve on the boards of such companies. The
Company hereby consents to such employment and to the Executive's service on the
boards of directors of other companies. During the period he is serving as
interim Chief Executive Officer of the Company, the Executive will receive
salary and bonus payments from Optimark, Inc. and the Company shall reimburse
Optimark, Inc. for a portion of such payments as agreed between the Company and
Optimark, Inc. The Executive shall be compensated for his duties as a member of
the board of directors of the Company (after he ceases to serve as Chief
Executive Officer) at the same rate as the other independent directors serving
on such board of directors. Any Company options previously granted to the
Executive pursuant to Section 2 shall be taken into account in determining the
Executive's compensation as a member of the Company's board of directors.

          2. Options. On or before September 15, 2002, the Company shall grant
to the Executive options to acquire a number of shares of the Company's common
stock ("Shares") equal to 0.5% of the Company's outstanding Shares on the date
of such grant. The exercise price of such options shall be the fair market value
per Share on the date of the grant as determined under the Company's 2002 Stock
Option Plan (the "Plan") and such options shall be fully vested on December 31,
2002, or, if earlier, upon the employment by the Company of a permanent Chief
Executive Officer. Such options shall be exercisable for a period of ten years
if the Executive remains a

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Service Provider (as defined in the Plan); provided, however, that any options
that are or become vested on the date of the termination of the Executive's
employment with the Company shall remain exercisable for a period of five years
from the date that the Executive shall cease to be a Service Provider. All of
the Company's options shall immediately vest upon a termination of the
Executive's employment with the Company prior to the earlier of (i) December 31,
2002 or (ii) the date the Company employs a permanent Chief Executive Officer,
unless such termination is as a result of a voluntary resignation by the
Executive or the Executive is terminated for Cause (as defined in the Plan), in
which case any unvested options shall thereupon automatically expire. Except as
specifically provided herein, the Executive's options shall be governed by the
terms and conditions of the Plan.

          3. Indemnification. The Company agrees that (i) if the Executive is
made a party, or is threatened to be made a party, to any threatened or actual
action, suit or proceeding, whether civil, criminal, administrative,
investigative, appellate or other (a "Proceeding") by reason of the fact that he
is or was a director, officer, employee, agent, manager, consultant or
representative of the Company or is or was serving at the request of the Company
or any of its Affiliates as a director, officer, member, employee, agent,
manager, consultant or representative of another person or (ii) if any claim,
demand, request, investigation, dispute, controversy, threat, discovery request
or request for testimony or information (a "Claim") is made, or threatened to be
made, that arises out of or relates to the Executive's service in any of the
foregoing capacities, then the Executive shall promptly be indemnified and held
harmless by the Company to the fullest extent legally permitted or authorized by
the Company's certificate of incorporation, bylaws or board resolutions or, if
greater, by the laws of the State of Delaware, against any and all costs,
expenses, liabilities and losses (including, without limitation, attorney's
fees, judgments, interest, expenses of investigation, penalties, fines, ERISA
excise taxes or penalties and amounts paid or to be paid in settlement) incurred
or suffered by the Executive in connection therewith, and such indemnification
shall continue as to the Executive even if he has ceased to be a director,
member, employee, agent, manager, consultant or representative of the Company or
other person and shall inure to the benefit of the Executive's heirs, executors
and administrators. The Company shall advance to the Executive all costs and
expenses incurred by him in connection with any such Proceeding or Claim within
15 days after receiving written notice requesting such an advance; provided,
however, that the Company shall not be required to provide the advance unless
the Company's insurance carrier has indicated that it will not pay for the costs
and expenses associated with such Proceeding or Claim. Such notice shall include
an undertaking by the Executive to repay the amount advanced if he is ultimately
determined to liable under such Proceeding or Claim. Prior to any advance, the
Executive shall post a bond sufficient to secure the amount advanced.

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          4. Miscellaneous. (a) Entire Agreement. This Agreement contains the
entire understanding and agreement between the Company and the Executive and
supersedes all prior agreements, understandings, discussions, negotiations and
undertakings, whether written or oral, between us with respect thereto.

             (b) Severability. In the event that any provision or portion of
this Agreement shall be determined to be invalid or unenforceable for any
reason, in whole or in part, the remaining provisions of this Agreement shall be
unaffected thereby and shall remain in full force and effect to the fullest
extent permitted by law so as to achieve the purposes of this Agreement.

             (c) Amendment or Waiver. No provision in this Agreement may be
amended unless such amendment is set forth in a writing signed by the parties.
No waiver by either party of any breach of any condition or provision contained
in this Agreement shall be deemed a waiver of any similar or dissimilar
condition or provision at the same or any prior or subsequent time. To be
effective, any waiver must be set forth in a writing signed by the waiving
party.

             (d) Headings. The headings of the Sections contained in this
Agreement are for convenience only and shall not be deemed to control or affect
the meaning or construction of any provision of this Agreement.

             (e) Governing Law/Jurisdiction. This Agreement shall be governed,
construed, performed and enforced in accordance with the laws of the State of
New York, without reference to principles of conflicts of laws.

             (f) Counterparts. This Agreement may be executed in two
counterparts, each of which shall be deemed an original, but all of which, when
taken together, shall constitute one and the same instrument.

          IN WITNESS WHEREOF, the undersigned have executed this Agreement as of
the date first set forth above.

          THE ASHTON TECHNOLOGY GROUP, INC.


          By:  /s/ William W. Uchimoto
               -----------------------------------
             Name:   William W. Uchimoto
             Title:  Executive Vice President & General Counsel

               /s/ Robert J. Warshaw
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               Robert J. Warshaw