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                                                                   EXHIBIT 10.15

               THIRD AMENDED AND RESTATED LIMITED WAIVER AGREEMENT


         THIS THIRD AMENDED AND RESTATED LIMITED WAIVER AGREEMENT (the
"Agreement") is made and entered into as of the 15th day of December, 1999, by
and between Software Spectrum, Inc., a Texas corporation (the "Company") and
Private Capital Management, Inc., a Florida corporation (the "Shareholder").
Terms used but not otherwise defined herein shall have the meanings assigned
them in the Rights Agreement, as defined in such agreement as referenced below.

                                   WITNESSETH:

         WHEREAS, the Company and ChaseMellon Shareholder Services, L.L.C., (the
"Rights Agent") (as successor to Keycorp Shareholder Services, Inc.), are
parties to that certain Rights Agreement, dated as of December 13, 1996 (the
"Rights Agreement"), which provides that, upon the event of any person or entity
becoming an "Acquiring Person" as defined therein (an "Event"), shareholders of
the Company may exercise certain Rights, defined therein to be the rights to
purchase from the Company certain shares of the preferred stock of the Company
having the rights and preferences set forth in the Statement of Designation
attached as Exhibit A to the Rights Agreement;

         WHEREAS, the Company and the Shareholder mutually agreed that it was in
the best interest of each of the Company and the Shareholder that the Company
effect a certain 1997 Stock Repurchase Plan (the "1997 Plan") pursuant to the
terms of which the Company from time to time during the operation of the 1997
Plan repurchased in the open market an amount equal to $2.5 Million, shares of
its common stock, par value $.01 (the "Common Stock") (the "1997 Plan
Repurchases");

         WHEREAS, in order to preclude the 1997 Plan Repurchases from resulting
in the Shareholder owning a percentage of the Company's stock that would result
in an Event (the "Shareholder Event"), which Shareholder Event, upon agreement
of the Company and the Shareholder, would have had undesirable consequences for
each of the Company and the Shareholder, the Company and the Shareholder
executed and delivered that certain Limited Waiver Agreement dated as of July
31, 1997 (the "Waiver Agreement");

         WHEREAS, following the completion of the 1997 Plan Repurchases, the
Company and the Shareholder mutually agreed that it was in the best interest of
each of the Company and the Shareholder that the Company effect a certain 1998
Stock Repurchase Plan (the "1998 Plan") pursuant to the terms of which the
Company from time to time during the operation of the 1998 Plan repurchased, for
an additional amount not to exceed in the aggregate $2.5 Million, in the open
market, a certain number of shares of its Common Stock (the "1998 Repurchases");

         WHEREAS, in order to preclude the 1998 Repurchases from resulting in
the Shareholder owning a percentage of the Company's Common Stock that would
result in a Shareholder Event,


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the Company and the Shareholder executed and delivered that certain Amended and
Restated Limited Waiver Agreement dated as of July 7, 1998 (the "Amended Waiver
Agreement");

         WHEREAS, following completion of the 1998 Repurchases, the Company and
the Shareholder mutually agreed that it was in the best interest of each of the
Company and the Shareholder that the Company effect a certain 1999 Stock
Repurchase Plan (the "1999 Plan") pursuant to the terms of which the Company
from time to time repurchased in the open market shares of the Company's common
stock up to an aggregate of $5.0 million (the "1999 Repurchases").

         WHEREAS, in order to preclude the 1999 Repurchases from resulting in
the Shareholder owing a percentage of the Company's Common Stock that would
result in a Shareholder Event, the Company and the Shareholder executed and
delivered that certain Second Amended and Restated Limited Waiver Agreement
dated as of March 29, 1999 (the "Second Amended Waiver Agreement").

         WHEREAS, the Company and the Shareholder have mutually agreed that upon
completion of the 1999 Repurchases, it is in the best interest of each of the
Company and the Shareholder that the Company effect a certain 2000 Stock
Repurchase Plan (the "2000 Plan") pursuant to the terms of which the Company
will from time to time during the operation of the 2000 Plan, repurchase for an
additional amount not to exceed $5.0 million, in the open market, a certain
number of shares of its Company Stock (the "2000 Repurchases"); and

         WHEREAS, the Company and the Shareholder have mutually agreed that it
is in the best interest of each of the Company and the Shareholder to amend and
restate the terms of the Second Amended Waiver Agreement, expressly to effect
the 2000 Plan;

         NOW, THEREFORE, in order to facilitate the 2000 Repurchases pursuant to
the 2000 Plan and simultaneously to preclude the occurrence of the Shareholder
Event, the Company and the Shareholder, in consideration of the mutual covenants
and agreements herein contained, do hereby agree as follows:

         1.       CERTAIN DEFINITIONS.

                  "Affiliate(s)" shall mean any person or entity that directly,
         or indirectly through one or more intermediaries, controls or is
         controlled by, or is under common control with, the Shareholder.
         Furthermore, with respect to the Shareholder, "Affiliate(s)" shall also
         mean any person or entity for whom the Shareholder acts as an
         investment advisor or consultant with respect to the Company.

                  "Beneficial Ownership" shall have the meaning assigned to such
         term in Rule 13d-3 of the General Rules and Regulations under the
         Securities Exchange Act of 1934, as amended as in effect on the date
         hereof.

                  "Control" shall mean the possession, direct or indirect, of
         the power to direct or cause the direction of the management and
         policies of the Company, whether through ownership of the Common Stock,
         by contract, or otherwise.

                                      -2-

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                  "Current Shareholder Position" shall have the meaning assigned
         it in Section 2 below.

                  "Prohibited Activity" shall mean: (i) any attempt by the
         Shareholder or any of its Affiliates to gain Control of the Company;
         (ii) any Prohibited Transaction, as hereinafter defined or (iii) any
         public action on the part of the Shareholder or any of its Affiliates,
         acting individually or in concert with other persons, which could
         reasonably be construed: (a) as an attempt to effect a change of
         Control including, but not limited to, the issuance of press releases
         or the filing of documents with the Securities And Exchange Commission
         or any other Federal or State governmental entity or (b) as an action
         contrary to the position of the then current board of directors of the
         Company.

                  "Prohibited Transaction" shall mean any transaction by the
         Shareholder or any of its Affiliates which would result in the
         Beneficial Ownership by the Shareholder or any of its Affiliates,
         either individually or as a group, of the Common Stock in an amount in
         excess of the Current Shareholder Position.

                  "Standstill Period" shall mean that time period commencing on
         the date of this Agreement and ending with the date which is the fifth
         annual anniversary of the date of this Agreement.

         2.       REPRESENTATIONS AND WARRANTIES OF THE COMPANY AND THE
SHAREHOLDER.

                  A. The Company hereby represents and warrants to the
Shareholder that it (i) has duly authorized the 2000 Plan and, subject to
relevant market and other factors and conditions affecting the Company in the
good faith judgment of its Board of Directors, the Company will make bona fide
efforts, during the operation of the 2000 Plan, to effect the 2000 Repurchases
pursuant to the 2000 Plan and (ii) is currently authorized to spend up to $5.0
Million on the 2000 Repurchases pursuant to the 2000 Plan.

                  B. The Shareholder hereby represents and warrants to the
Company that, as of the date hereof, the total number of shares of Common Stock
of which the Shareholder or any of its Affiliates or Associates has Beneficial
Ownership is 861,854 shares (as such share ownership may be affected from time
to time by stock splits, stock dividends, reverse splits or any other such
matter affecting all shareholders equally, the "Current Shareholder Position").

         3.       CERTAIN COVENANTS AND AGREEMENTS.

                  A. Covenants and Agreements of the Company.

                           a. The Company hereby agrees that, notwithstanding
the fact that the 2000 Repurchases pursuant to the 2000 Plan may result in the
Shareholder Event, if the Shareholder Event should occur solely by virtue of the
1997 Plan Repurchases, the 1998 Repurchases, the 1999 Repurchases and/or the
2000 Repurchases pursuant to the 2000 Plan, such Shareholder Event shall be
deemed not to have occurred, and the Company hereby grants a limited waiver of
any provision of the Rights Agreement pursuant to the terms of which the
Shareholder Event would be considered

                                      -3-

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to have occurred solely by virtue of the 1997 Plan Repurchases, the 1998
Repurchases, the 1999 Repurchases and/or the 2000 Repurchases.

                           b. The Company hereby acknowledges and agrees that,
by virtue of the operation of this Agreement, the Shareholder, alone or together
with its Affiliates and Associates, may have Beneficial Ownership of twenty
percent (20%) or more of the shares of Common Stock of the Company then
outstanding, provided that such circumstance occurs solely as a result of the
1997 Plan Repurchases, the 1998 Repurchases Repurchases, the 1999 Repurchases
and/or the 2000 Repurchases, and yet not be deemed to be an "Acquiring Person"
for purposes of the Rights Agreement.

                           c. The Company acknowledges and agrees that nothing
in this Agreement shall preclude the Shareholder from (i) effecting sales and
purchases of the Common Stock so long as the Current Shareholder Position is not
exceeded or (ii) subject to the provisions of paragraph 3(B)(a) below,
exercising the voting privileges commensurate with its ownership of the Common
Stock.

                  B. Covenants and Agreements of the Shareholder.

                           a. The Shareholder agrees that neither the
Shareholder nor any of its Affiliates shall engage in any Prohibited Activity
(i) at any time that the Shareholder, alone or together with its Affiliates has
Beneficial Ownership of 20% or more of the outstanding Common Stock of the
Company as a result of Repurchases pursuant to any of the repurchase Plans, or
(ii) during the Standstill Period.

                           b. The Shareholder acknowledges and agrees that this
Agreement constitutes only a limited waiver of the Rights Agreement and that the
waiver herein contained applies only to the occurrence of the Shareholder Event
as the result solely of the 1997 Plan Repurchases, the 1998 Repurchases, the
1999 Repurchases and/or the 2000 Repurchases and not to any other circumstances
or conditions which may result in the occurrence of the Shareholder Event.

                           c. The Shareholder hereby further acknowledges that,
should the Shareholder Event occur as a result of or in connection with the
purchase or acquisition by the Shareholder of Common Stock of the Company which
results in an increase in the Current Shareholder Position, then this limited
waiver shall not apply and the Shareholder shall, in accordance with the terms
of the Rights Agreement, be deemed to be an "Acquiring Person."

                  C. Covenants and Agreements of the Company and the
Shareholder.

                     The Company and the Shareholder acknowledge and agree that
this Agreement constitutes a limited waiver of the Rights Agreement; by agreeing
to this waiver, the Company has not agreed to waive any other provisions of the
Rights Agreement and the Company hereby expressly reserves its right fully to
enforce the Rights Agreement except as such enforcement may be limited by the
express terms of this Agreement.

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         4.       GENERAL PROVISIONS.

                  A. Voidability. This Agreement shall become null and void if
the Company shall not have publicly announced its authorization of the 2000 Plan
on or before January 31, 2000.

                  B. Entire Agreement. This Agreement constitutes the entire
agreement by and among the parties with respect to the subject matter hereof.

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

                  D. Assignability. This Agreement shall be binding upon and
inure to the benefit of the successors and assigns of the parties hereto;
provided, that neither this Agreement nor any right hereunder shall be
assignable by the Shareholder without the prior written consent of the Company
and the Rights Agent, but this Agreement shall be assignable by the Company to
any successor by merger or otherwise to the Company and by the Rights Agent to
any successor without the consent of the Shareholder.

                  E. Governing Law. The validity, interpretation and effect of
this Agreement shall be governed exclusively by the laws of the State of Texas.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above written.

                                                  SOFTWARE SPECTRUM, INC.


                                                  By:   /s/ JUDY ODOM SIMS
                                                        -----------------------
                                                  Name:     Judy Odom Sims
                                                        -----------------------
                                                  Title:    Chairman & CEO
                                                        -----------------------

                                                  PRIVATE CAPITAL MANAGEMENT,
                                                  INC.


                                                  By:   /s/ GREGG J. POWERS
                                                        -----------------------
                                                  Name:     Gregg J. Powers
                                                        -----------------------
                                                  Title:    President, Private
                                                        -----------------------
                                                            Capital Mgt., Inc.
                                                        -----------------------


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ACKNOWLEDGED AND ACCEPTED:

CHASEMELLON SHAREHOLDER SERVICES, L.L.C.


By:   /s/ R. JOHN DAVIS
      ----------------------------------
Name:     R. John Davis
      ----------------------------------
Title:    Vice President
      ----------------------------------



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