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                                                                   EXHIBIT 10.37

                         Form of Clarification letter


                                                       November 30, 1999

[name]
[address]

     Re:  Clarification regarding your capital commitment of $[__________]
          pursuant to that certain Letter Agreement (the "Letter Agreement"),
          dated as of September 10, 1999 (with an effective date of September
          10, 1999), between you and ZEFER Corp. (the "Company").

Dear [name]

     In light of the Company's recent restructuring of its available financing,
including the re-characterization of a portion of GTCR's capital commitments to
the Company (i.e., from an equity capital commitment for senior preferred stock
to a debt-based capital commitment of equal size), the Company is sending this
letter of clarification to you with respect to your ongoing rights and
obligations under the Letter Agreement.

     On September 10, 1999, you accepted the Company's invitation to invest in
the Company by making a capital commitment to the Company of up to $[__________]
on the terms and conditions set forth in the Letter Agreement. This acceptance
was later memorialized in the Letter Agreement referenced above.  In particular,
the Letter Agreement provides that:

          "By agreeing to the foregoing capital commitment, you will be entitled
          to purchase [______] shares of ZEFER common stock at a price of
          $[____] per share and will be required to purchase up to [___] shares
          of ZEFER's senior preferred stock at a price of $1000.00 per share
          from time to time as the Company receives funding in respect of its
          capital commitments from GTCR Golder Rauner LLC ("GTCR"). . . . By
          making this capital commitment, you will be required to fund 19% of
          your commitment [initially] and to make additional purchases on a pro
          rata basis with GTCR as additional funds are needed by the Company."

     Although it is clear from this language that the restructuring described
above does not affect any of your rights or obligations under the Letter
Agreement (including your obligation to make additional purchases of the
Company's senior preferred stock on a pro rata basis with GTCR at such times as
the Company receives funding in respect of GTCR's capital commitments), it is
equally clear that, after giving effect to such restructuring, the example set
forth in the second paragraph of the Letter Agreement, which only makes
reference to GTCR's capital commitment for senior preferred stock (but not
GTCR's new debt-based capital commitment), no longer serves as an accurate
illustration of your "additional purchase" obligation under the Letter
Agreement.  Rather, as of the restructuring, the example set forth in the Letter
Agreement should be revised to illustrate that you will be required to make
additional purchases of the Company's senior preferred stock
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pursuant to the terms of the Letter Agreement at such times as the Company
receives funding in respect of any GTCR capital commitment (including GTCR's
debt-based capital commitment).

     As such, in the interest of clarity for both you and the Company going
forward, please acknowledge your receipt and acceptance of this letter by
signing in the space provided below and returning the same by facsimile to the
undersigned at 617-451-8001 by December 3, 1999.  Please call if you have any
questions regarding this letter and thank you for your continued support of the
Company.

                                                  Sincerely,


                                                  Sean W. Mullaney
                                                  Executive Vice President
                                                    and General Counsel

ACCEPTED AND AGREED TO:

By:
       ----------------------------------
Name:
       ----------------------------------


     This Form of Clarification Letter was issued to and accepted by the
executives of the Registrant (or the affiliates thereof) listed below. The only
material differences among the respective Investment Letters are the following:

     (i)    the aggregate dollar amount of the capital commitment,
     (ii)   the number of shares of common stock and preferred stock to be
            purchased, and
     (iii)  the per share purchase price for the common stock.


The table below sets forth the above information with respect to each such
executive.


                                   Total          Total          Common
                    Aggregate      Common       Preferred       Purchase
Executive           Investment     Shares         Shares         Price
---------           ----------     ------         ------         -----
Carol Boudreau      $350,978       71,868           339          $0.17

Gerry Dube          $314,443       61,692           291          $0.38

Mellaney
Investments, LLC    $200,855       41,128           194          $0.17

James Slamp         $104,814       20,564            97          $0.38

Martha Stephens     $100,427       20,564            97          $0.17

Frank Torbey        $100,427       20,564            97          $0.17

Thomas Waite        $145,876       28,620           135          $0.38

David Lubin         $174,971       35,828           169          $0.17

Richard Nolan       $100,427       20,564            97          $0.17