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                                                          Exhibit 10.9
                                                Chicago Mercantile Exchange Inc.
                                              Registration Statement on Form S-4


                             EMPLOYMENT AGREEMENT
                             --------------------

     This Employment Agreement ("Agreement") is entered into by and between the
CHICAGO MERCANTILE EXCHANGE ("CME") and FREDERICK ARDITTI ("Arditti") this
27th day of October, 1998.

     WHEREAS, the parties desire to enter into this Agreement pertaining to the
employment of Arditti by the CME;

     NOW, THEREFORE, in consideration of the mutual promises and covenants set
forth below, the parties hereby agree as follows:

     1.   Employment. Subject to the terms of this Agreement, the CME hereby
agrees to employ Arditti during the Agreement Term as Senior Executive Vice
President-Planning and Development, and Arditti hereby accepts such employment.
Arditti shall report directly to the President of the CME. As Senior Executive
Vice President-Planning and Development, Arditti shall be responsible for new
business development and have overall responsibility for the following
departments and/or operations of the CME: Clearing; Marketing; Research and
Strategic Planning; and such other duties as may be assigned to him by the
President or Board of Directors of the CME. These duties may be changed from
time-to-time as determined by the President or Board of Directors of the CME,
provided that any such duties shall be consistent with the position of Executive
Vice President. During his employment, Arditti agrees to devote his full time,
energies and talents to serving as Senior Executive Vice President-Planning and
Development of the CME, and to perform his duties faithfully, efficiently and in
good faith, subject to the direction of the President and Board of Directors of
the CME.
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     2.   Agreement Term. The Agreement Term shall be from July 1, 1998 through
June 30, 2001. Unless renewed by the mutual written agreement of the parties,
this Agreement will automatically terminate upon the expiration of the Agreement
Term. The CME will give Arditti written notice of its intention to renew or not
renew or to renegotiate the terms of the Agreement at least sixty (60) days
prior to expiration. In the absence of renewal, upon expiration of this
Agreement, Arditti shall be an employee of the CME working without a contract.

     3.   Compensation. During the Agreement Term and while employed by the CME,
the CME shall compensate Arditti as follows:

          a. Base Salary. Arditti shall be paid an annual base salary of Five
Hundred Thousand Dollars ($500,000.00), payable in equal bi-weekly installments.
Annual increases, if any, shall be as determined by the CME in accordance with
its policies and practices with respect to executive compensation.

          b. Benefits. Subject to their terms, Arditti and any of his eligible
dependents shall be entitled to participate in all fringe benefits and benefit
plans of the CME under the same terms and conditions as are generally
applicable to the employees and officers of the CME as those fringe benefits
and benefit plans currently exist and/or as they may be amended from time to
time during the Agreement Term. Such benefit plans shall specifically include,
without limitation, the Chicago Mercantile Exchange Senior Management Supplement
Deferred Savings Plan and the Chicago Mercantile Exchange Supplemental Executive
Retirement Plan.

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     c.   Bonus. Subject to its terms, Arditti shall participate in the CME's
discretionary bonus program.

     4.   Termination. Arditti's employment with the CME during the Agreement
Term may be terminated only under the following circumstances:

          a. Death. Arditti's employment hereunder will terminate upon his
death.

          b. Disability. If Arditti is disabled, and receiving benefits under
the CME's long term disability insurance program, the obligations under this
Agreement shall be suspended for the duration of such disability. In the event
Arditti returns to the position set forth herein during the term of this
Agreement, the provisions of this Agreement shall be reinstated. In the event
Arditti returns to work in a different position, or does not return to work at
all upon conclusion of his disability, this Agreement shall be deemed
terminated.

          c. Cause. Arditti's employment hereunder may be immediately terminated
by the CME for cause. For purposes of this Agreement, "cause" shall be defined
as misconduct, incompetence, failure to perform and/or neglect of duties which
is gross or willful, and shall include actions by Arditti which occur outside of
the CME which would have a substantial likelihood of bringing significant
discredit upon the CME.

          d. Termination by Arditti. This Agreement may be terminated by Arditti
at any time and for any reason by the giving of at least sixty (60) days advance
written notice of same to the CME.

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     5.   Payments Upon Termination or Expiration.

          a. In the event of termination of Arditti pursuant to Paragraphs 4a or
4b of this Agreement, the CME shall for a period of six (6) months following
such termination continue Arditti's base salary (or pay same to his estate).

          b. In the event of termination of Arditti by the CME pursuant to
Paragraph 4(c) of this Agreement, or upon expiration of the Agreement Term, the
CME shall continue Arditti's base salary, less applicable deductions for state
and federal taxes, and health insurance for a period of three (3) months, and
shall pay to Arditti any vacation pay which is accrued but unused as of the date
of his termination.

          c. In the event of termination by Arditti pursuant to Paragraph 4.d of
this Agreement, and provided that such termination does not take place prior to
April 1, 2000, the CME shall continue Arditti's base salary for a period one (1)
year following such termination. In the event Arditti terminates this Agreement
pursuant to Paragraph 4d herein with less than the sixty (60) days advance
written notice of same, the parties acknowledge that the CME will be damaged
thereby, but that such damages will be difficult to calculate. Accordingly,
Arditti will promptly pay to the CME, or allow set off against any monies it may
then owe to Arditti, as liquidated damages a sum equal to his base salary,
computed daily, for each day his notice of termination under Paragraph 4(d) is
less than sixty (60) days.

     6.   DePaul University. During his employment by the CME, Arditti has been
and is on a leave of absence from his position as a tenured member of the
faculty at DePaul University in Chicago, Illinois. In order to maintain his
tenure, Arditti must declare by March, 1999, whether he intends to return to the
faculty of DePaul University. The CME

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agrees to assist Arditti to have the date of such declaration extended from
March, 1999 to March, 2000, with the manner and means of such assistance to be
determined solely by the CME.

     7.   Confidentiality. Arditti acknowledges that in his employment he is or
will be making use of, acquiring or adding to the CME's Confidential Information
which includes (but is not limited to) memoranda and other materials or records
of a proprietary nature; technical data, records and policy matters relating to
new business development, research, strategy, finance, accounting, marketing,
personnel, clearing, management, and operations. Therefore, in order to protect
such Confidential Information and to protect other employees who depend on the
CME for regular employment, Arditti agrees that he will not during or after the
term of his employment in any way utilize any of said Confidential Information,
except in connection with his employment by the CME, and he will not copy,
reproduce, or take with him the original or any copies of said Confidential
Information and he will not disclose any of said Confidential Information to
anyone. Further, Arditti agrees to advise any new employer of the terms of this
Agreement regarding Confidential Information. These restrictions regarding
Confidential Information shall be in addition to those which exist at common law
or by statute.

     8.   Arbitration; Equitable Remedies.

     Any controversy or claim arising out of or relating to this Agreement or
the validity, interpretation, enforceability or breach thereof, which is not
settled by agreement of the parties, shall be settled by arbitration conducted
in the City of Chicago, in accordance with the Rules of the American Arbitration
Association, and judgment upon the award rendered in

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such arbitration may be entered in any court having jurisdiction. The
arbitration shall he conducted before a single arbitrator selected by the
parties. In the event the parties cannot agree on an arbitrator, then the
Association will supply both parties with a list of seven names. The parties
will alternatively strike one name until only one remains. First choice will be
determined by a coin toss, the winning party having the option of striking
first. All expenses of arbitration shall be borne equally by the parties, except
for attorneys' fees which shall be borne entirely by each party. The arbitrator
shall have no power to amend, alter, add to or delete from this Agreement.

     Arditti acknowledges that the CME would be irreparably injured by a
violation of Paragraph 7 and he agrees that the CME, in addition to any other
remedies available to it for such breach or threatened breach, shall be entitled
to a preliminary injunction, temporary restraining order, or other equivalent
relief, restraining Arditti from any actual or threatened breach of Paragraph 7
pending and in aid of arbitration of the dispute. If a bond is required to be
posted in order for the CME to secure an injunction or other equitable remedy,
the parties agree that such bond need not be more than a nominal sum.

     9.   Return of Property. Upon his last day of active work, Arditti hereby
agrees to immediately turn over to the CME any keys, credit cards, passes, and
all notes, memoranda, records, documents, computer disks, and all other
information, no matter how produced or reproduced, kept by Arditti or in his
possession or control, used in or pertaining to the business of the CME, it
being hereby acknowledged that all of said items are the sole and exclusive
property of the CME.

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     10.  Defense of Claims. During the period of his employment by the CME, and
for periods after the termination of his employment, Arditti shall reasonably
cooperate with the CME at its request in the defense or prosecution of any claim
that may be made by or against the CME. Such cooperation shall include, without
limitation, serving as a witness at trial or hearing, being deposed, and
preparation for same. For the period after Arditti terminates his employment
with the CME, the CME shall reimburse Arditti for all reasonable expenses in
connection therewith, including travel expenses, and shall compensate him at a
daily rate equal to the greater of his then current annual base salary or his
annual base salary on the date his employment with the CME terminates, divided
by 260, with days used for preparation, travel and other related matters being
included for purposes of determining the compensation due to Arditti. Less than
full days shall be paid for by the hour, determined by dividing the daily rate
by eight. To the extent reasonably practicable, the CME shall provide Arditti
with notice at least ten days prior to the date on which any such travel is
required.

     11.  Nonalienation. The interests of Arditti under this Agreement are not
subject in any manner to anticipation, alienation, sale, transfer, assignment,
pledge, encumbrance, attachment, or garnishment by creditors of Arditti or
Arditti's beneficiaries.

     12.  Amendment. This Agreement may be amended or cancelled only by the
subsequent mutual written agreement of the parties.

     13.  Applicable Law. The provisions of this Agreement shall be construed in
accordance with the laws of the State of Illinois, without regard to the
conflict of law provisions of any state.

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     14.  Waiver of Breach. No waiver of any party hereto of a breach of any
provision of this Agreement by any other party, or of compliance with any
condition or provision of this Agreement to be performed by such other party,
will operate or be construed as a waiver of any subsequent breach by such other
party or any similar or dissimilar provisions and conditions at the same or any
prior or subsequent time. The failure of any party hereto to take any action by
reason of such breach will not deprive such party of the right to take action at
any time while such breach continues.

     15.  Notices. Notices and all other communications provided for in this
Agreement shall be in writing and shall be delivered personally or sent by
registered or certified mail, return receipt requested, postage prepaid, or sent
by facsimile or prepaid overnight courier to the parties at, respectively, the
business address of the CME and the home address of Arditti (or to Arditti at
the business address of the CME if Arditti is employed there at the time of
such notice). Such notices and other communications shall be deemed given:

          a. in the case of delivery by overnight service with guaranteed next
day delivery, the next day or the day designated for delivery;

          b. in the case of certified or registered U.S. mail, five days after
deposit in the U.S. mail; or

          c. in the case of facsimile, the date upon which the transmitting
party received confirmation of receipt by facsimile, telephone or otherwise;
provided, however, that in no event shall any such communications be deemed to
be given later than the date they are actually received.

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     16.  Severability. If any provision, section, subsection or other portion
of this Agreement shall be determined by any court of competent jurisdiction to
be invalid, illegal or unenforceable in whole or in part, and such determination
shall become final, such provision or portion shall be deemed to be severed or
limited, but only to the extent required to render the remaining provisions and
portions of this Agreement enforceable. This Agreement as thus amended shall be
enforced so as to give effect to the intention of the parties insofar as that is
possible. In addition, the parties hereby expressly empower a court of competent
jurisdiction to modify any term or provision of this Agreement to the extent
necessary to comply with existing law and to enforce this Agreement as modified.

     17.  Survival of Agreement; Successors. Except as otherwise expressly
provided in this Agreement, the rights and obligations of the parties to this
Agreement shall survive the termination of Arditti's employment with the CME. In
the event of a merger, sale, reorganization or other change of control, this
Agreement shall be binding upon and inure to the benefit of any successor of the
CME.

     18.  Entire Agreement. This Agreement constitutes the entire agreement
between the parties concerning the subject matter hereof and supersedes all
prior and contemporaneous agreements, if any, between the parties relating to
the subject matter hereof.

     19.  Counterparts. This Agreement may be signed in multiple counterparts,
each of which shall be deemed to be an original for all purposes.

     20.  Acknowledgment by Arditti. Arditti represents that he is knowledgeable
and sophisticated as to business matters, including the subject matter of this
Agreement, that he has read this Agreement and that he understands its terms.
Arditti acknowledges that, prior to

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assenting to the terms of this Agreement, he has been given a reasonable time to
review it, to consult with counsel of his choice, and to negotiate at arm's-
length with the CME as to the contents. Arditti and the CME agree that the
language used in this Agreement is the language chosen by the parties to express
their mutual intent, and that no rule of strict construction is to be applied
against any party hereto.

     IN WITNESS WHEREOF, the parties have executed this Agreement on the date(s)
set forth below.

                               CHICAGO MERCANTILE EXCHANGE



                               By  /s/ Gerald D. Beyer
                                  ---------------------------------
                               Title  Executive Vice President
                                     ------------------------------
                               Date  10-27-98
                                    -------------------------------


                               /s/ Frederick Arditti
                               ------------------------------------
                               Frederick Arditti

                               Date  10-27-98
                                    -------------------------------

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                    FIRST AMENDMENT TO EMPLOYMENT AGREEMENT
                    ---------------------------------------


     Reference is hereby made to the Employment Agreement entered into between
the CHICAGO MERCANTILE EXCHANGE ("CME") and FREDERICK ARDITTI ("Arditti") on
October 27, 1998 ("Agreement").

The Agreement is hereby amended as follows:

1.   4.d. Termination by Arditti.

     Paragraph 4.d. is hereby deleted and replaced in its entirety with the
following provision:

     This Agreement may be terminated by Arditti at any time and for any reason.

2.   Subparagraph c of Paragraph 5. Payments Upon Termination or Expiration.

Subparagraph c of Paragraph 5 is hereby deleted and replaced in its entirety
with the following provision.

     In the event of termination by Arditti pursuant to Paragraph 4.d of this
Agreement, and provided that such termination does not take place prior to
April 1, 2000, the CME shall continue Arditti's base salary for a period of one
(1) year following such termination. In addition, Arditti will receive at the
time of such termination, a lump sum payment, in cash, equal to his then-current
non-vested amounts in the following plans: Tax Efficient Savings Plan (401K
Plan); Pension Plan for Employees of the Chicago Mercantile Exchange; Senior
Management Supplemental Deferred Savings Plan; and Supplemental Executive
Retirement Plan.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
set forth below.

CHICAGO MERCANTILE EXCHANGE

By:   /s/ Scott Gordon
      ----------------------------
      Scott Gordon, Chairman
Date: January 7, 2000

      /s/ Fred D. Arditti
      ----------------------------
By:   Frederick Arditti
Date: January 7, 2000
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                   SECOND AMENDMENT TO EMPLOYMENT AGREEMENT
                   ----------------------------------------


     Reference is hereby made to the Employment Agreement entered into between
the CHICAGO MERCANTILE EXCHANGE ("CME") and FREDERICK ARDITTI ("Arditti") on
October 27, 1998 ("Agreement").

     The Agreement is hereby amended as follows:

1.   Subparagraph c of Paragraph 5. - Payment Upon Termination or Expiration.

     Subparagraph c of Paragraph 5 is hereby deleted and replaced in its
     entirety with the following provision.

     In the event of termination by Arditti pursuant to Paragraph 4.d of this
     Agreement, and provided that such termination does not take place prior to
     April 1, 2000, the CME shall:

     (i)   continue Arditti's base salary for a period of one (1) year following
           such termination (the "Continuation Period");

     (ii)  pay Arditti, at the time of such termination, a lump sum payment, in
           cash, equal to his then-current non-vested amounts in the following
           plans: Tax Efficient Savings Plan (401K Plan); Pension for Employees
           of the Chicago Mercantile Exchange; Senior Management Supplemental
           Deferred Savings Plan; and Supplemental Executive Retirement Plan.

     (iii) during, the Continuation Period, provide Arditti and any covered
           dependents with continued coverage under the CME's health, dental and
           vision insurance program in effect for active employees; provided,
           however, that effective at the end of the Continuation Period,
           health, dental and vision insurance benefits will be provided to
           Arditti and any covered dependents pursuant to the Consolidated
           Omnibus Budget Reconciliation Act ("COBRA"), as set forth in Section
           4980B of the Internal Revenue Code of 1986, as amended, and in
           Sections 601 through 609 of the Employee Retirement Income Security
           Act. Arditti's contribution and the CME's contribution toward the
           cost of the foregoing coverages shall be determined and paid as
           though Arditti's employment with the CME continued through the end
           of the Continuation Period. The foregoing insurance coverages will
           earlier terminate upon Arditti obtaining other employment which
           offers comparable health insurance coverage and when he first becomes
           eligible for such coverage. Arditti agrees that he will promptly
           notify the CME upon obtaining such coverage from another employer.
           Arditti shall have no duty to seek or obtain other employment.

     (iv)  during the Continuation Period, and subject to CME's discretion,
           either reimburse Arditti for the cost of converting the above-
           referenced life and accidental death and dismemberment insurance
           programs in effect on the date of Arditti's termination to individual
           coverage, or obtaining
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          equivalent coverage individually, or, where applicable, continuing
          individual coverage already in place. It is understood and agreed that
          Arditti's coverage under the CME's disability insurance plan will
          cease on the date of Arditti's termination and that the CME has no
          obligation to provide or pay for other disability coverage. The CME
          will cooperate with Arditti, (e.g., providing documentation) in his
          efforts to obtain at his expense individual disability coverage.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
set forth below.

CHICAGO MERCANTILE EXCHANGE


By:   /s/ Scott Gordon
      ----------------------------
      Scott Gordon, Chairman
Date: February 3, 2000

      /s/ Fred D. Arditti
      ----------------------------
By:   Frederick Arditti
Date: February 3, 2000