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                                                                      Exhibit 2A

                                AMENDMENT NO. 1

                                      TO

                           STOCK PURCHASE AGREEMENT


     This Amendment No. 1 (the "Amendment") to the Stock Purchase Agreement
dated as of May 11, 2000 (the "Agreement"), by and among ePresence, Inc., a
Massachusetts corporation (the "Buyer"), Strategic Network Designs, Inc., a
New Jersey corporation ("SND") and the stockholders of SND, is entered into as
of this 9th day of June, 2000. Capitalized terms used herein and not otherwise
defined shall have the same meaning as in the Agreement.

     WHEREAS, pursuant to Section 5.9 of the Agreement, the Buyer was to obtain
the release of any personal guarantees of David Rovner or Ranjan Sinja within
thirty (30) days from the Closing Date, or cause any borrowings by SND from
First Union to be repaid in full;

     WHEREAS, the parties desire to extend the time period within which the
Buyer may obtain such releases;

     WHEREAS, Section 10.11 provides for written amendments to the Agreement;
and

     NOW THEREFORE, for good and valuable consideration, the receipt of which is
hereby acknowledged, the parties hereto to amend Section 5.9 by deleting the
terms "thirty (30)" and replacing "forty-five (45)" therefor.

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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment, as a
sealed document, as of the date set forth above.


                                       ePRESENCE, INC.


                                       /s/ Richard M. Spaulding
                                       ------------------------------------
                                       By:  Richard M. Spaulding
                                       Title:  Sr. Vice President & CFO


                                       STOCKHOLDERS' REPRESENTATIVE


                                       /s/ Ranjan Sinja
                                       ------------------------------------
                                       By:   Ranjan Sinja


                                       2
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                                AMENDMENT NO. 2

                                      TO

                           STOCK PURCHASE AGREEMENT


     This Amendment No. 2 (the "Amendment") to the Stock Purchase Agreement
dated as of May 11, 2000 (the "Agreement"), by and among ePresence, Inc., a
Massachusetts corporation (the "Buyer"), Strategic Network Designs, Inc., a
New Jersey corporation ("SND") and the stockholders of SND, is entered into as
of this 26th day of June, 2000. Capitalized terms used herein and not otherwise
defined shall have the same meaning as in the Agreement.

     WHEREAS, pursuant to Section 5.9 of the Agreement, the Buyer was to obtain
the release of any personal guarantees of David Rovner or Ranjan Sinja within
thirty (30) days from the Closing Date, or cause any borrowings by SND from
First Union to be repaid in full;

     WHEREAS, pursuant to Amendment No. 1 to Stock Purchase Agreement, dated
June 9, 2000, the time period within which the Buyer may obtain such releases
was extended from thirty (30) days to forty-five (45) days;

     WHEREAS, the parties desire to further extend the time period within which
the Buyer may obtain such releases; and

     WHEREAS, Section 10.11 provides for written amendments to the Agreement.

     NOW THEREFORE, for good and valuable consideration, the receipt of which is
hereby acknowledged, the parties hereto to amend Section 5.9 by deleting the
terms "forty-five (45)" and replacing "fifty-nine (59)" therefor.

                                       1
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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment, as a
sealed document, as of the date set forth above.


                                       ePRESENCE, INC.


                                       /s/ Richard M. Spaulding
                                       ------------------------------------
                                       By:  Richard M. Spaulding
                                       Title:  Sr. Vice President & CFO


                                       STOCKHOLDERS' REPRESENTATIVE


                                       /s/ Ranjan Sinja
                                       ------------------------------------
                                       By:   Ranjan Sinja

                                       4
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                                AMENDMENT NO.3

                                      TO

                           STOCK PURCHASE AGREEMENT

     This Amendment No. 3 (the "Amendment") to the Stock Purchase Agreement
dated as of May 11, 2000, and as amended on June 9, 2000 and on June 26, 2000
(the "Agreement"), by and among ePresence, Inc. a Massachusetts corporation
(the "Buyer"), Strategic Network Designs, Inc., a New Jersey corporation ("SND")
and the stockholders of SND, is entered into this 26th day of March, 2001 by and
among the Buyer, David R. Rovner and Ranjan Sinha, acting individually and as
the Stockholders' Representative, (collectively the "Parties"). Capitalized
terms used herein and otherwise not defined shall have the same meaning as in
the Agreement.

     WHEREAS, Section 1.2(b)(i) of the Agreement provides for a Contingent
Payment if certain Performance Based Targets are achieved by the SND Business
Unit;

     WHEREAS, the Parties wish to amend the Agreement subject to the terms and
provisions hereof;

     WHEREAS, Section 10.11 allows for written amendments to the Agreement; and

     NOW THEREFORE, for good and valuable consideration, the receipt of which is
hereby acknowledged by each of the Parties hereto, and with the intent to be
bound, the Parties hereto agree as follows:

1.  Section 1.2(b)(i) of the Agreement shall be deleted in its entirety and the
following shall be inserted in lieu thereof:

     "(b)  (i)  Buyer agrees to make a cash payment in the amount of $2,075,000
to the Stockholders (in accordance with the ownership percentages set forth in
Schedule I to the Agreement) in compromise and full settlement of the Contingent
Payment (such payment to be made within 3 business days of full execution and
delivery of this Amendment).  It is further agreed that the Stockholders, after
consulting with its legal counsel, hereby release, discharge and forever waive
any and all claims, known and unknown, that it ever had, now has or might have
against the Buyer and its affiliates and the directors, officers, shareholders,
and employees, agents, attorneys, successors and assigns respectively of each
arising from, or related to the Contingent Payment in any manner whatsoever,
including, without limitation, under Sections 5.2 or 5.3 of the Agreement."

2.  Sections 1.2(b)(ii), 1.2(b)(iii) and 1.2(c) and Schedule II thereto shall be
deleted in their entirety.

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3.  Ranjan Sinha represents and warrants to the Buyer that Ranjan Sinha has the
power and authority to execute this Amendment as Stockholders' Representative
and that this Amendment is a valid and binding agreement of the Stockholders,
enforceable in accordance with its terms.

4.  Except as otherwise expressly provided by this Amendment, all of the terms,
conditions and provisions of the Agreement shall remain in full force and
effect.  This Amendment may be executed in any number of counterparts, but all
such counterparts shall together constitute but one instrument.  In making proof
of this Amendment it shall not be necessary to produce or account for one more
than one counterpart signed by each party hereto and against which enforcement
hereof is sought.

5.  This Amendment shall be construed according to and governed by the internal
laws of the Commonwealth of Massachusetts without reference to principles of
conflicts of law.


     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as a
sealed document, as of the date set forth above.


                                       ePRESENCE, INC.


                                       /s/ Richard M. Spaulding
                                       --------------------------------------
                                       Richard M. Spaulding
                                       Title: Senior Vice President and CFO


                                       /s/ Ranjan Sinha
                                       -------------------------------------
                                       Ranjan Sinha, individually and as
                                       Stockholders' Representative


                                       /s/ David R. Rovner
                                       --------------------------------------
                                       David R. Rovner

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