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                                                                   EXHIBIT 10.21

March 13, 2000

Ms. Johna Till Johnson
221 East 33/rd/ Street Apt. 6-F
New York, NY 10016

Dear Johna:

This letter agreement (this "Agreement") when executed by both you and Greenwich
Technology Partners, Inc. (the "Company"), shall confirm the understanding
between you and the Company relating to your employment by the Company, and
shall supercede all prior agreements between you and the Company.

We are very proud of our corporate culture.  We believe that open communication
between the Company and its employees and treating each other fairly and with
respect are critical to our success and to creating an environment in which we
are able to enjoy our work.  Consequently, we want your assurance that should
there ever come a time during your employment with the Company that you are
dissatisfied with any aspect of your employment, you will communicate such
dissatisfaction to the person to whom you directly report, or, if that is not
comfortable for you, to any other manager of the Company, including the Chief
Executive Officer.


1.   Major Terms
     -----------

     A.   Services
          --------

          You shall serve and your title shall be Chief Technology Officer of
          the Company.  In that capacity, you shall report directly to the Chief
          Executive Officer of the Company.  As Chief Technology Officer of the
          Company, you will have executive responsibility for (i) developing and
          implementing the strategic direction of the Company in connection
          with, among other things, technology investments, strategic
          partnerships and new product and service offers, with other senior
          executives of the Company; (ii) representing the Company's technology
          strategies, expertise and direction to all third parties, including,
          without limitation, the Company's current, future and prospective
          customers, members of the press and industry analysts; (iii) working
          with the Company's current, future and prospective customers to define
          and develop new product and service offerings; and (iv) those other
          functions customary to your position and title.
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          While you are employed by the Company, you will devote your entire and
          exclusive business and professional time, attention, energy, loyalty
          and skill to the business of the Company to the best of your ability.
          In addition, you will use your reasonable efforts to preserve for the
          Company the goodwill of customers and others with whom the Company
          establishes business relationships during your employment and to
          advance the reputation of the Company.  You shall comply with and
          perform such directions and duties in relation to the business and
          affairs of the Company consistent with your title and position as are
          requested of you by the Company.  While you are employed by the
          Company your principal place of employment shall be the New York City
          Metropolitan Area (as such term is customarily defined) (the
          "Principal Place of Employment").

     B.   Compensation
          ------------

          In consideration of all of the services to be rendered by you to the
          Company pursuant to this Agreement, the Company will pay to you a base
          salary of $150,000 per annum (the "Base Salary").  Your Base Salary
          shall be payable on the 15th and 30th day of each month in arrears,
          pro rated for the initial period worked.  The Company shall have the
          right to deduct from your compensation all taxes and other normal and
          customary payroll deductions and withholdings required by applicable
          law.  Your Base Salary and Bonus (as defined below) shall be reviewed
          at least annually by a member of senior management to ascertain
          whether such Base Salary and Bonus should be increased.  Pursuant to
          Connecticut Wage laws, you are an exempt employee and therefore not
          eligible under State requirements to receive overtime pay.

          Bonus:  So long as you are employed by the Company, you will receive a
          ------
          guaranteed bonus of $12,500 per annum, payable on July 15 of each year
          and an additional annual bonus of up-to $37,500, or $50,000 in the
          aggregate, based on MBO's jointly developed by you and Company (the
          "Bonus").

          Expenses:  The Company shall pay or reimburse you for all reasonable
          ---------
          expenses actually incurred or paid by you, in the course of your
          employment with the Company.

          Home Office and Computer Allowance:  The Company shall provide you
          -----------------------------------
          with home office and computer equipment allowance in the amount up to
          $2,000 per annum.

          Tools and Resources:  During the course of your employment with the
          --------------------
          Company, the Company shall provide to you, at the Company's sole cost
          and expense, all tools and resources necessary for you to perform your
          duties and functions, including, without limitation, those tools and
          resources set forth as Exhibit A attached hereto.

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     C.   Options
          -------

          You shall be entitled to participate in the Company's 1997 Stock
          Option Plan (the "Plan") to the same extent as other senior executives
          of the Company.  Subject to the approval of the Company's Board of
          Directors you shall initially be granted options to purchase up to
          125,000 shares of the Company's common stock (the "Options"), par
          value $0.01 per share, at an exercise price equal to the fair market
          value of the Company's common stock per share on the Commencement Date
          (as defined in Section 1D hereof), but in no event greater than $0.60
          per share.  The Options shall vest and become exercisable as follows:
          25% of the Options shall vest and become exercisable on the first
          anniversary of the Commencement Date, and the remainder of the Options
          shall vest and become exercisable ratably on the first day of each
          month after the first anniversary date of the Commencement Date over
          the following three years.  The Options shall be subject to the terms
          of the Plan and to such other terms and conditions as may be specified
          by the Company in the form of a standard option agreement between the
          Company and you, subject, however to the immediately proceeding
          sentence.  In the event that the your employment with the Company is
          terminated by the Company without "Cause", or you resign with "Good
                                    -------                        ----
          Reason" (as such terms are defined in Section 8 of the Agreement) at
          any time prior to the first anniversary of the Commencement Date, the
          vesting of the Options shall accelerate, and 25% of the Options shall
          immediately vest and you shall be entitled to exercise such Options
          for a period of equal to three months after the date of such
          termination or resignation, as the case may be.

     D.   Commencement Date; Termination
          ------------------------------

          Your employment shall commence on or around April 1, 2000 (the
          "Commencement Date").  Your employment may be terminated by you with
          or without Good Reason or by the Company with or without Cause at
          anytime.  Neither this Agreement, any employee handbook, or any other
          document of the Company gives you any contractual right, either
          express or implied, to remain in the employ of the Company.
          Notwithstanding the foregoing, in the event you resign because of the
          failure of the Company to grant to you the Options on the terms set
          forth in this Agreement prior to the first anniversary date of the
          Commencement Date, the Company shall pay to you as severance within 30
          days after the effective date of such resignation a lump sum payment
          in the amount equal to your Base Salary from the effective date of
          such resignation up-to the first anniversary date of the Commencement
          Date and that portion of your Bonus theretofore earned but unpaid,
          including, without limitation, any guaranteed payments (the "Severance
          Payment").  Furthermore, in such event, you shall be under no
          obligation to seek other employment and there shall be no off-set
          against the Severance Payment on account of any renumeration
          attributable to any subsequent employment you may obtain.

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     E.   Use of Company Property
          -----------------------

          You will not use the Company's premises, facilities, or equipment for
          personal purposes.

     F.   Moonlighting and Competitive Activity
          -------------------------------------

          You covenant and agree that, during non-business hours, you shall not
          engage in any activity related to, competitive with, or in the
          business of, the Company, without the prior written consent of the
          Company.  Such activities shall include, but not be limited to
          designing intranet or internet networks, network consulting,
          maintenance, repair, troubleshooting or systems design and/or
          installation (a "Competitive Activity").  If you are unsure whether a
          particular activity would violate the aforesaid covenant, you shall
          seek the advice of a senior officer of the Company.  You hereby accept
          said employment and agree faithfully to perform said duties and render
          said services for the term of your employment.

2.   Right to Change Pay Practices, Policies, Procedures and Benefits.  The
     ----------------------------------------------------------------
     Company shall have the right, at any time without prior notice, to change,
     modify, amend, or terminate any pay practice, employment policy or
     procedure, or employment benefit plan or program in effect upon the
     commencement of your employment or adopted subsequently. You will be
     entitled to participate on the same basis as other senior executives of the
     Company in all the Company's benefits available to other senior executives
     employees in similar positions of the Company, including, without
     limitation, medical and dental coverage, a 401K plan, short term and long
     term disability, life insurance, and those other benefits and privileges
     set forth on Exhibit B attached hereto. You shall be covered by and named
     as an additional insured under the Company's Director's and Officers
     Liability Insurance Policy.

3.   Representations and Warranties.  You represent and warrant that:  you are
     ------------------------------
     not under any obligation to any third party which could interfere with your
     performance under this letter agreement; and your performance of your
     obligations to the Company during your employment with the Company will not
     breach any agreement by which you are bound not to disclose any proprietary
     information.

4.   Inventions.
     ----------

     i.   You will as soon as practicable disclose to the Company all Inventions
          (as herein defined). "Inventions" shall mean all ideas, potential
          marketing and sales relationships, inventions, research, plans for
          products and services, marketing plans, software (including, without
          limitation, source code), know-how, trade secrets, information, data,
          developments, discoveries, improvements, modifications, technology,
          and designs, whether or not subject to patent or copyright protection,
          made, conceived, expressed, developed, or actually or constructively
          reduced to practice by you solely or jointly with others during your
          employment with the Company, which refer to, are suggested by, or
          result

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          from any work which you may do during your employment, or from any
          information obtained from the Company.

     ii.  The Inventions shall be the exclusive property of the Company, and are
          hereby assigned by you to the Company; the Company shall have the
          exclusive right to use the Inventions for all purposes without
          additional compensation to you. At the Company's expense, you will
          assist the Company in every proper way to protect the Inventions
          throughout the world, including, without limitation, executing in
          favor of the Company patent, copyright, and other applications and
          assignments relating to the Inventions.

5.   Confidential Information.
     -------------------------

     i.   You will not disclose, give, sell, publish or otherwise use, either
          during your employment by the Company or after the termination of your
          employment, except in the performance of your duties for the benefit
          of the Company, any Confidential Information (as herein defined).
          "Confidential Information" shall mean, all of the Company's
          proprietary information, technical data, technology, process, trade
          secrets, and know-how, other intellectual property rights, strategies,
          financial statements or other financial information, forecasts,
          operations, business plans, prices, discounts, products, product
          specifications, designs, plans data, ideas or information contained in
          the Company's Business Strategy Overview and Career Advancement Manual
          which is disclosed to you, which you may acquire or develop, or which
          you may observe in the course of your employment by the Company and
          which at the time of disclosure is not previously known by you and not
          known or used by others in the trade generally, does not become
          generally available to the trade through no fault of yours, and does
          not become rightfully available to you on a non-confidential basis
          from a source other than the Company, including, without limitation,
          research, product plans, customer lists, markets, software,
          developments, inventions, processes, formulas, technology, designs,
          drawings, marketing and other plans, and financial data and
          information. "Confidential Information" shall also mean information
          received by the Company from customers of the Company or other third
          parties subject to a duty to keep confidential and financial, pricing,
          and credit information regarding customers, clients, or vendors of the
          Company. Upon termination of your employment, you shall promptly
          deliver to the Company, in whatever form or medium, all files,
          drawings, blueprints, specifications, reports, notebooks, and other
          materials containing any Confidential Information which are in you
          possession or control.

6.   Restrictive Covenants.
     ---------------------

     A.   Covenants Against Competition and Solicitation.
          ----------------------------------------------

          Commencing on the Commencement Date and continuing thereinafter for a
          period of 90 days from the date of termination of your employment with
          the Company by either (i) the Company for Cause or (ii) by you without
          Good

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          Reason, without the prior written consent of the Company, you will
          not, directly or indirectly:

          i.   persuade or attempt to persuade any customer, client, supplier or
               distributor of the Company to cease doing business with the
               Company, or to reduce the amount of business it does with the
               Company;

          ii.  persuade or attempt to persuade any potential customer, client,
               supplier or distributor to which the Company has made a
               presentation, or with which the Company had been having
               discussions, not to do business with the Company;

          iii. persuade or attempt to persuade any employee of the Company to
               leave the employ of the Company;

          iv.  Become retained by or employed by, as an employee or consultant
               or otherwise undertake with any other person, individual or
               corporation, joint venture, or other business arrangement, which
               directly competes with the business of the Company.

     B.   Geographic Scope.
          -----------------

          For purposes of paragraph 6A, the geographic scope of the restrictive
          covenants contained therein, shall be 150 miles from your Principal
          Place of Employment.

7.   Injunctive Relief and Severability.
     -----------------------------------

     i.   You agree that the remedy at law for any breach of the provisions of
          this letter agreement shall be inadequate and the Company shall be
          entitled to injunctive or other equitable relief in addition to any
          other remedy it might have.

     ii.  The Company and you agree and acknowledge that the covenant not to
          compete and the right of first refusal described are made in
          consideration of substantial compensation payable under this letter
          agreement. In consequence of this the Company and you agree and
          acknowledge that the duration, scope, and geographic area included in
          such covenant not to compete are fair, reasonable, necessary, and
          appropriate, and will not prevent you from engaging in profitable
          business activities or employment. Nevertheless, should a court
          determine that such duration, scope, or geographic areas are not
          reasonable, such restrictions shall be interpreted, modified, or
          rewritten to include as much of such duration, scope, or geographic
          areas as will render such restrictions valid and enforceable.

     iii. The Company and you intend to and do hereby confer jurisdiction to
          enforce this letter agreement upon the courts of any jurisdiction
          within the geographical scope of the agreements contained therein. In
          the event that the courts of any one or more of such jurisdictions
          shall hold such agreements wholly or partly unenforceable by reason of
          the breadth of such scope or otherwise, it is the intention of the
          Company and you that such determination shall not bar or in any

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          way affect the Company's right to relief hereunder in the courts of
          any other jurisdiction within the geographical scope of any such
          agreement, as to breaches of such agreements in such other respective
          jurisdictions, the above agreements as they relate to each
          jurisdiction being, for this purpose, severable into independent
          agreements.

8.   Certain Definitions.
     -------------------

     As used in this Agreement, the following terms shall have the following
     meanings:

     Termination for "Cause" shall mean termination of your employment with the
     Company because of (i) your conviction of a felony involving fraud, theft
     or moral turpitude; (ii) the willful or persistently repeated material non-
     performance of your duties to the Company (other than by reason of
     incapacity due to your physical or mental illness), provided that you
     receive a detailed written notice describing such non-performance and the
     same continues after you receive such written notice; and (iii) any
     material breach by you of a material term of this Agreement, which breach
     is not cured within 5 business days after written notice to you specifying
     such breach.  Termination of your employment for Cause shall be
     communicated by delivery to you of a written notice from the Company
     stating that the Executive has been terminated for Cause, specifying the
     particulars thereof and the effective date of such termination.

     Resignation for "Good Reason" shall mean resignation by Executive because
     of (i) an adverse and material change in your duties, titles or reporting
     responsibilities; (ii) a breach by the Company of any term of this
     Agreement; (iii) a reduction in your Base Salary or bonus opportunity or
     the failure of the Company to pay you any amount of compensation when due;
     (iv) a relocation of your Principal Place of Employment without your prior
     written consent; (v) an assignment of this Agreement by the Company,
     whether by operation of law or otherwise; (vi) the failure of the Board of
     Directors of the Company to approve and/or the failure of the Company to
     grant the Options on the terms set forth in this Agreement on or prior to
     June 1, 2000; or (vii) a "Change of Control" (as defined below) in the
     Company.  The Company shall have 5 business days from the date of receipt
     of such notice to effect a cure (if curable) of the material breach
     described therein.  The date of termination of employment without Cause
     shall be the date specified in a written notice of termination to the
     Executive.  The date of resignation for Good Reason shall be the date
     specified in a written notice of resignation from the Executive to the
     Company; provided, however, that no such written notice shall be effective
     unless the cure period specified in the immediately preceding sentence has
     expired without the Company having corrected, to the satisfaction of the
     Executive, the event or events subject to cure.

     "Change of Control" shall be deemed to have occurred if (i) in connection
     with a merger or acquisition of the Company, at least 50% of the voting
     stock of the Company is transferred to persons or entities which are not
     stockholders of the Company on the date hereof; (ii) the sale, lease or
     exchange of all or substantially all the assets of the Company; or (iii)
     the Company is to be dissolved or liquidated.

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9.   Severability.
     ------------

     In the event any of the provisions of this letter agreement shall be held
     by a court or other tribunal of competent jurisdiction to be unenforceable,
     the other provisions of this letter agreement shall remain in full force
     and effect.

10.  Survival.
     --------

     All terms and conditions of this letter agreement which should by their
     nature survive the termination of your employment with the Company shall so
     survive.

11.  Governing Law.
     -------------

     This letter shall be governed by, construed and enforced in accordance with
     the internal laws of the State of New York governing agreements made and to
     be fully performed therein, without giving effect to conflict of law
     principles.

12.  Notices.
     -------

     All notices, requests, consents and other communications required or
     permitted hereunder shall be in writing and shall be hand delivered or
     mailed by certified or registered mail, return receipt requested, addressed
     as follows:

     i.   if to the Company, at Greenwich Technology Partners, Inc., 43
          Gatehouse Road, Stamford, CT 06902, Attention: Director of Legal
          Affairs.

     ii.  if to you, at the address set forth above or in any such case, at such
          other addresses as may have been furnished to any party by the other
          party in writing in the manner herein provided. Any notice or other
          communication so addressed and so mailed shall be seemed to have been
          given when mailed, and if hand delivered shall be deemed to have been
          given when delivered.

13.  Waivers and Modifications.
     -------------------------

     This letter agreement may be modified, and the rights and remedies of any
     provision hereof may be waived, only in writing, signed by each of the
     Company, and you.  No waiver by either party of any breach by the other of
     any provision hereof shall be deemed to be a waiver of any later or other
     breach thereof or as a waiver of any such or other provision of this letter
     agreement.  This agreement sets forth all of the terms of the
     understandings between the parties with reference to the subject matter set
     forth herein may not be waived, changed, discharged or terminated orally or
     by any course of dealing between the parties, but only by an instrument in
     writing signed by the party against whom any waiver, change, discharge or
     termination is sought.  Each of the Company and you hereby acknowledges and
     agrees that any prior arrangements, agreements or understandings relating
     to your employment with the Company and/or any of its affiliates is hereby
     terminated and extinguished in its entirety.

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14.  Assignment.
     ----------

     This Agreement shall be binding upon and inure to the benefit of the
     Company and its successors and assigns.  This Agreement is not assignable
     by you and your right to receive payment for your services is hereby
     expressly agreed to be non-assignable and nontransferable, except as
     otherwise specifically provided herein.

Sincerely,

/s/ Joseph Beninati

Joseph Beninati
Chairman & CEO

I have carefully read the terms and conditions of the above and acknowledge and
accept the terms and conditions of this letter agreement.

Please sign, date and return this offer letter prior to your start date.

Name:  /s/ Johna Till Johnson
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       Johna Till Johnson

Date:  03/13/00
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