EX-10.1: WAIVER AND GENERAL RELEASE

Exhibit 10.1

WAIVER AND GENERAL RELEASE

September 13, 2006

Thomas M. Thees
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Dear Tom:

     This Waiver and General Release (this “ Agreement ”) serves to memorialize the terms of the termination of your employment with MARKETAXESS CORPORATION (“ MarketAxess ”). The terms of this Agreement, including your right to the payments and benefits referred to in Paragraph 2 below, are contingent upon and subject to your executing and not revoking this Agreement. As used in this Agreement, the terms “ you ” and “ your ” refer to Thomas M. Thees.

      1. Termination of Employment .

     You hereby acknowledge and agree that your employment with MarketAxess was terminated effective September 12, 2006 (the “ Termination Date ”).

      2. Severance Payments and Benefits .

     Subject to your full compliance with all of your obligations under this Agreement, including but not limited to the covenants contained in Paragraphs 3 and 4, in addition to payment of all unpaid compensation and benefits earned by you through the Termination Date:

     (a) You will continue to be paid your current semi-monthly pay, Eight Thousand, Three Hundred Thirty Three dollars and Thirty Three cents ($8,333.33) per pay period (less standard applicable tax withholdings and other deductions required by law), for a period of four (4) weeks from the Termination Date (the “ Severance Pay ”);

     (b) You will be paid a bonus of Four Hundred Twenty-Five Thousand Dollars ($425,000.00) (less standard applicable tax withholdings and other deductions required by law), which shall be paid to you at the time bonuses are paid to MarketAxess’ senior executive officers, but not later than January 31, 2007 (the “ Severance Bonus ”);

     (c) Subject to you not engaging in Competition (as defined in the Proprietary Information and Non-Competition Agreement between you and MarketAxess dated February 8, 2005 (the “Non-Competition Agreement”)) on or prior to September 14, 2007, you will be paid an additional lump sum severance payment on September 14, 2007 in the amount of Three Hundred Eighty-Nine Thousand Five Hundred dollars ($389,500.00) (less standard applicable tax withholdings and other deductions required by law) (the “ Lump Sum Severance Payment ”);

     (d) You will be eligible to continue your coverage under MarketAxess’ group medical and dental insurance plans, if currently elected, as in effect on the Termination Date for a period of four weeks from the Termination Date (the “ Coverage Continuation ” and, together with the Severance Pay, the Lump Sum Severance Payment and the Severance Bonus, the “ Severance Benefits ”); provided however, that the Coverage Continuation will terminate when you become covered by health insurance offered by another employer. After the expiration of the Coverage Continuation, you will be entitled to continue your health coverage under MarketAxess’ group medical and dental insurance plans, if currently elected, at your sole expense in accordance with the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended, for 18 months.

      3. Employee’s General Release and Waiver .

     (a) YOU HEREBY RELEASE MARKETAXESS AND ALL OF ITS AFFILIATES, AND ITS AND THEIR RESPECTIVE OFFICERS, DIRECTORS, SENIOR MANAGERS, SHAREHOLDERS, MEMBERS, EMPLOYEES, SUCCESSORS AND ASSIGNS (COLLECTIVELY REFERRED TO HEREIN AS THE “ RELEASEES ”), JOINTLY AND SEVERALLY, FROM ANY AND ALL CLAIMS, KNOWN OR UNKNOWN, WHICH YOU OR YOUR HEIRS, SUCCESSORS OR ASSIGNS HAVE OR MAY HAVE AGAINST ANY RELEASEE ARISING ON OR PRIOR TO THE DATE THAT YOU EXECUTE THIS AGREEMENT AND ANY AND ALL LIABILITY WHICH ANY SUCH RELEASEE MAY HAVE TO YOU, WHETHER DENOMINATED CLAIMS, DEMANDS, CAUSES OF ACTION, OBLIGATIONS, DAMAGES OR LIABILITIES ARISING FROM ANY AND ALL BASES, HOWEVER DENOMINATED, INCLUDING BUT NOT LIMITED TO CLAIMS FOR WRONGFUL DISCHARGE, ACCRUED BONUS OR INCENTIVE PAY, THE AGE DISCRIMINATION IN EMPLOYMENT ACT, THE AMERICANS WITH DISABILITIES ACT OF 1990, THE FAMILY AND MEDICAL LEAVE ACT OF 1993, TITLE VII OF THE UNITED STATES CIVIL RIGHTS ACT OF 1964, 42 U.S.C. § 1981, WORKERS ADJUSTMENT AND RETRAINING NOTIFICATION ACT, THE NEW YORK HUMAN RIGHTS LAW, INCLUDING NEW YORK EXECUTIVE LAW § 296, § 8-107 OF THE ADMINISTRATIVE CODE AND CHARTER OF NEW YORK CITY OR ANY OTHER FEDERAL, STATE OR LOCAL LAW. THIS RELEASE IS FOR ANY AND ALL CLAIMS, INCLUDING BUT NOT LIMITED TO CLAIMS ARISING FROM AND DURING YOUR EMPLOYMENT RELATIONSHIP WITH MARKETAXESS AND ITS AFFILIATES OR AS A RESULT OF THE TERMINATION OF SUCH RELATIONSHIP. NOTWITHSTANDING ANY PROVISION CONTAINED IN THIS AGREEMENT, THIS RELEASE IS NOT INTENDED TO INTERFERE WITH YOUR RIGHT TO FILE A CHARGE WITH THE EQUAL EMPLOYMENT OPPORTUNITY COMMISSION IN CONNECTION WITH ANY CLAIM YOU BELIEVE YOU MAY HAVE AGAINST ANY OF THE RELEASEES. HOWEVER, BY EXECUTING THIS AGREEMENT, YOU HEREBY WAIVE THE RIGHT TO RECOVER IN ANY PROCEEDING YOU MAY BRING BEFORE THE EQUAL EMPLOYMENT OPPORTUNITY COMMISSION OR ANY STATE HUMAN RIGHTS COMMISSION OR IN ANY PROCEEDING BROUGHT BY THE EQUAL EMPLOYMENT OPPORTUNITY COMMISSION OR ANY STATE HUMAN RIGHTS COMMISSION ON YOUR BEHALF. THIS RELEASE IS FOR ANY RELIEF, NO MATTER HOW DENOMINATED, INCLUDING, BUT NOT LIMITED TO, INJUNCTIVE RELIEF, WAGES, BACK PAY, FRONT PAY, COMPENSATORY DAMAGES, OR PUNITIVE DAMAGES. THIS RELEASE SHALL NOT APPLY TO ANY OBLIGATION OF MARKETAXESS PURSUANT TO THIS AGREEMENT.

     YOU ACKNOWLEDGE THAT THE SEVERANCE BENEFITS THAT YOU WILL RECEIVE UNDER PARAGRAPH 2 OF THIS AGREEMENT REPRESENT GOOD AND VALUABLE CONSIDERATION FOR YOUR ENTERING INTO THIS AGREEMENT TO WHICH YOU OTHERWISE DID NOT HAVE A RIGHT.

     (b) In the event there is presently pending any action, suit, claim, charge or proceeding with any federal, state or local court or agency relating to any claim within the scope of Paragraph 3(a), or if such a proceeding is commenced in the future, you shall, to the extent permitted by law, promptly withdraw it, with prejudice, to the extent that you have the power to do so.

     (c