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                                                                    EXHIBIT 10.1

                          SECURITIES PURCHASE AGREEMENT

         THIS SECURITIES PURCHASE AGREEMENT is made as of September 28, 2001, by
and among AVIDYN, Inc., a Delaware corporation (the "Company"), The Answer
Partnership, Ltd., a Texas limited partnership (the "Partnership"), The
Essential Endowment Trust (the "Trust") and J. Ward Hunt ("Mr. Hunt").

                                    RECITALS:

         WHEREAS, the Partnership is owned 62.5% by John Ward Hunt and 37.5% by
the Trust;

         WHEREAS, the Partnership intends to distribute 993,040 shares of Common
Stock, $0.01 par value ("AVIDYN Stock") to the Trust and the Trust intends to
withdraw from the Partnership prior to the Closing (as defined below);

         WHEREAS, the Partnership desires to sell and the Company desires to
purchase 106,960 shares of AVIDYN Stock and the Trust desires to sell and the
Company desires to purchase 993,040 shares of AVIDYN Stock.

                                   AGREEMENT:

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants set forth in this Agreement, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

         1. Basis of Exchange.

         1.1 Purchase and Sale of Securities. Pursuant to the terms and
conditions of this Agreement, the Partnership agrees to sell and deliver to the
Company 106,960 shares of AVIDYN Common Stock (the "TAP Shares") and the Company
agrees to purchase, accept and receive from the Partnership, the TAP Shares.
Pursuant to the terms and conditions of this Agreement, the Trust agrees to sell
and deliver to the Company 993,040 shares of AVIDYN Common Stock (the "Trust
Shares") and the Company agrees to purchase, accept and receive from the Trust,
the Trust Shares.

         1.2 Purchase Price. The purchase price per share for the Tap Shares and
the Trust Shares is $3.60 per share.

         1.3 Closing. The closing of the sale of the TAP Shares and the Trust
Shares (the "Closing") shall be held at a mutually acceptable time on or before
October 15, 2001. At the Closing, the Partnership shall deliver to the Company
the TAP Shares with appropriate stock powers and the Trust shall deliver to the
Company the Trust Shares with appropriate stock powers. At the Closing, the
Company shall pay the Partnership $385,056 and the Trust $3,574,944 by wire
transfer or company check. At the Closing and as a condition of the Closing, (i)
Mr. J. Ward Hunt and the Company must consummate the proposed transaction
wherein Mr. Hunt cancels his options to purchase 500,000 shares of AVIDYN Stock
and the Company pays Mr. Hunt $5,000 in consideration thereof and (ii) Mr. J.
Ward Hunt's salary and benefit shall be decrease by the compensation committee
of the Board of Directors of the Company to an amount equal to the President of
the Company.



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         2. Representations.

         2.1 The Company hereby represents to the Partnership and the Trust that
this Agreement has been duly authorized, executed and delivered by the Company,
and is the legal, valid and binding obligation of the Company enforceable in
accordance with its terms except that (i) enforceability may be limited by
bankruptcy, insolvency or other similar laws affecting creditors' rights and
(ii) the availability of equitable remedies may be limited by equitable
principles of general applicability.

         2.2 The Trust hereby represents to the Company that this Agreement has
been duly authorized, executed and delivered by the Trust, and is the legal,
valid and binding obligation of the Trust enforceable in accordance with its
terms except that (i) enforceability may be limited by bankruptcy, insolvency or
other similar laws affecting creditors' rights and (ii) the availability of
equitable remedies may be limited by equitable principles of general
applicability.

         2.3 The Partnership hereby represents to the Company that this
Agreement has been duly authorized, executed and delivered by the Partnership,
and is the legal, valid and binding obligation of the Partnership enforceable in
accordance with its terms except that (i) enforceability may be limited by
bankruptcy, insolvency or other similar laws affecting creditors' rights and
(ii) the availability of equitable remedies may be limited by equitable
principles of general applicability.

         3. Indemnification.

         3.1 Mr. Hunt and the Partnership (each an "Indemnifying Party") jointly
and severally hereby agree to indemnify and defend the Company and its officers,
directors, partners, employees, agents, successors and assigns (each an
"Indemnified Party") from and against (a) any and all damages, losses,
settlement payments, obligations, liabilities, claims, actions or causes of
action and encumbrances suffered, sustained, incurred or required to be paid by
an Indemnified Party to or in connection with (i) the Partnership, (ii) any
partner of the Partnership, (iii) the Trust, (iv) the beneficiaries of the Trust
or the estate or relatives of the beneficiaries of the Trust, (v) the trustees
of the Trust, or (vi) the successor or assigns of the Partnership, the partners
of the Partnership, the Trust, the beneficiaries of the Trust or the trustees of
the Trust, or (b) all reasonable costs and expenses (including, without
limitation, attorneys' fees, interest and penalties) incurred by Indemnified
Party in connection with any action, suit, proceeding, demand, assessment or
judgment incident to any of the matters indemnified against in this Section 3.

         3.2 The obligations and liabilities of Indemnifying Party hereunder
with respect to claims resulting from the assertion of liability by Indemnified
Party shall be subject to the following terms and conditions:

         (a) Indemnified Party shall give prompt written notice to Indemnifying
Party of any claim which might give rise to a claim by Indemnified Party against
Indemnifying Party based on the indemnity agreement contained in the Section
3(a), stating the nature and basis of said claims and the amounts thereof, to
the extent known;

         (b) If any action, suit or proceeding is brought against Indemnified
Party with respect to which Indemnifying Party may have liability under the
indemnity agreement contained in Section 3(a), the action, suit or proceeding
shall, upon the written acknowledgment by Indemnifying Party that it is
obligated to indemnify under such indemnity agreement, be defended (including
all proceedings on appeal or for review which counsel for Indemnified Party
shall deem appropriate) by Indemnifying Party.



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Indemnified Party shall have the right to employ its own counsel in any such
case, but the fees and expenses of such counsel shall be at Indemnified Party's
own expense unless the employment of such counsel and the payment of such fees
and expenses both shall have been specifically authorized in writing by
Indemnifying Party in connection with the defense of such action, suit or
proceeding. Indemnified Party shall be kept fully informed of such action, suit
or proceeding at all stages thereof whether or not separate counsel represents
it.

         (c) Indemnified Party shall make available to Indemnifying Party and
its attorneys and accountants all books and records of Indemnified Party
relating to such proceedings or litigation and the parties hereto agree to
render to each other such assistance as they may reasonably require of each
other in order to ensure the proper and adequate defense of any such action,
suit or proceeding.

         (d) Indemnified Party shall not make any settlement of any claims
without the prior written consent of Indemnifying Party, which consent shall not
be unreasonably withheld or delayed. Indemnifying Party shall not make any
settlement of any claims which may adversely affect Indemnified Party without
the prior written consent of Indemnified Party, which consent shall not be
unreasonably withheld or delayed.

         (e) Except as herein expressly provided, the remedies provided in
Section 3 hereof shall be cumulative and shall not preclude assertion by any
party of any other rights or the seeking of any other rights or remedies against
any other party hereto.

         4. Miscellaneous Provisions.

         4.1 Amendment. This Agreement may be amended at any time but only by an
instrument in writing signed by the parties hereto.

         4.2 Assignment. This Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors, heirs and
assigns.

         4.3 Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

         4.4 Entire Agreement. This Agreement contains the entire understanding
of the Company and the Purchasers in respect of the subject matter contained
herein. This Agreement supersedes any prior agreements and understandings
between the parties with respect to the subject matter.

         4.5 Notices. Any notice, consent, demand, request, approval or other
communication to be given hereunder by any party to another shall be deemed to
have been duly given if given in writing and personally delivered or sent by
overnight delivery service, telegram, facsimile transmission, telex or United
States mail, registered or certified, postage prepaid, with return receipt
requested, to that set forth under the parties' signature hereto. Notice so
given shall, in the case of notice so given by mail, be deemed to be given and
received on the fourth calendar day after posting, in the case of notice so
given by overnight delivery service, on the date of actual delivery and, in the
case of notice so given by telegram, facsimile transmission, telex or personal
delivery, on the date of actual transmission or, as the case may be, personal
delivery.



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         4.6 Third-Party Beneficiaries. This Agreement is intended for the
parties hereto, and no other person or entity shall have any rights,
obligations, duties and benefits pursuant hereto.

         4.7 Governing Law. This Agreement shall be governed by and construed
under the laws of the State of Texas.

         IN WITNESS WHEREOF, the Company, the Partnership and the Trust have
executed this Agreement as of the date first written above.


                                          AVIDYN, INC.

Address:
16980 Dallas Parkway, Suite 120
Dallas, Texas 75248                       By:      /s/ Joseph A. Hensley
                                             -----------------------------------
                                             Joseph A. Hensley, President

                                          The Answer Partnership, Ltd
Address:
16980 Dallas Parkway, Suite 120
Dallas, Texas 75248                       By:      /s/ J. Ward Hunt
                                             -----------------------------------
                                             J. Ward Hunt, Managing Partner

Address:                                  The Essential Endowment Trust
P. O. Box 7594
Dallas, Texas  75209-7594
                                          By:      /s/ Hilre Lucille Hunt
                                             -----------------------------------
                                             Hilre Lucille Hunt, Trustee

Address:
16980 Dallas Parkway, Suite 120                    /s/ J. Ward Hunt
Dallas, Texas 75248                       --------------------------------------
                                          J. Ward Hunt




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