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                                                                     EXHIBIT 4.1

                               PURCHASE AGREEMENT

         This PURCHASE AGREEMENT (this "Agreement"), dated as of December 28,
2001, is entered into by and between The viaLink Company, a Delaware corporation
(the "Company"), and each of the Purchasers whose names are set forth on Exhibit
A hereto (individually, a "Purchaser" and collectively, the "Purchasers"), for
the purchase and sale of shares of the Company's Series C Convertible Preferred
Stock, par value $.001 per share (the "Preferred Stock"), in the manner, and
upon the terms, provisions and conditions set forth in this Agreement.

         WHEREAS, the parties desire that, upon the terms and subject to the
conditions contained herein, the Company shall issue and sell to the Purchasers
and Purchasers shall purchase shares of Preferred Stock; and

         WHEREAS, such purchase and sale will be registered under the United
States Securities Act of 1933, as amended (the "Securities Act"), pursuant to
the Registration Statement (as defined in Section 3(c) hereof).

         NOW, THEREFORE, in consideration of the representations, warranties and
agreements contained herein and other good and valuable consideration, the
receipt and legal adequacy of which is hereby acknowledged by the parties, the
Company and the Purchasers hereby agree as follows:

1.       Purchase Price.

         1.1.     Upon the following terms and subject to the conditions
                  contained herein, the Purchasers hereby agree to purchase an
                  aggregate of 600 shares of the Company's Preferred Stock (the
                  "Preferred Shares"), convertible into shares of the Company's
                  common stock, par value $.001 per share (the "Common Stock"),
                  at a per share price of $10,000 and for an aggregate purchase
                  price of $6,000,000 (the "Purchase Price"). The designation,
                  rights, preferences and other terms and provisions of the
                  Series C Convertible Preferred Stock are set forth in the
                  Certificate of Designation of the Relative Rights and
                  Preferences of the Series C Convertible Preferred Stock
                  attached hereto as Exhibit B (the "Certificate of
                  Designation").

         1.2.     Upon the following terms and subject to the conditions
                  contained herein, the Purchasers shall be issued Series A
                  Warrants, in substantially the form attached hereto as Exhibit
                  C (the "Series A Warrants"), and SDS Merchant Fund, L.P.
                  ("SDS") shall be issued Series B Warrants, in substantially
                  the form attached hereto as Exhibit D (the "Series B
                  Warrants," and together with the Series A Warrants, the
                  "Warrants"), to purchase the number of shares of Common Stock
                  set forth opposite such Purchaser's name on Exhibit A hereto.
                  The Warrants shall have an exercise price equal to the Warrant
                  Price (as defined in the applicable Warrant) and shall have a
                  term of five years. The Series A Warrants shall be immediately
                  exercisable and the

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                  Series B Warrants shall become exercisable upon consummation
                  of the Second Closing (as defined in Section 1(e) hereof).

         1.3.     The Company has authorized and has reserved and covenants to
                  continue to reserve, free of preemptive rights and other
                  similar contractual rights of stockholders, a sufficient
                  number of its authorized but unissued shares of Preferred
                  Stock to effect the issuance of the Preferred Shares.

         1.4.     The Company has authorized and has reserved and covenants to
                  continue to reserve, free of preemptive rights and other
                  similar contractual rights of stockholders, a sufficient
                  number of its authorized but unissued shares of Common Stock
                  to effect the conversion of the Preferred Stock and exercise
                  of the Warrants. Any shares of Common Stock issuable upon
                  conversion of the Preferred Stock and exercise of the Warrants
                  (and such shares when issued) are herein referred to as the
                  "Conversion Shares" and the "Warrant Shares," respectively.
                  The Preferred Shares, the Conversion Shares and the Warrant
                  Shares are sometimes collectively referred to as the "Shares."

         1.5.     The Company agrees to issue and sell to the Purchasers and, in
                  consideration of and in express reliance upon the
                  representations, warranties, covenants, terms and conditions
                  of this Agreement, the Purchasers, severally but not jointly,
                  agree to purchase that number of the Preferred Shares and
                  Warrants set forth opposite their respective names on Exhibit
                  A and subject to the terms and conditions hereof, consummate
                  each of the Closings (as defined below). The Purchase Price of
                  the Preferred Shares and Warrants being acquired by each
                  Purchaser is set forth opposite such Purchaser's name on
                  Exhibit A. The Preferred Shares and Warrants shall be sold and
                  funded in two separate closings (each, a "Closing"). The
                  initial closing under this Agreement (the "Initial Closing")
                  shall take place upon execution of this Agreement by a date no
                  later than December 31, 2001 (the "Initial Closing Date") and
                  shall be funded in the amount of $3,000,000. The second
                  closing under this Agreement (the "Second Closing") shall take
                  place no later than March 25, 2002 (the "Second Closing Date")
                  and shall be funded in the amount of $3,000,000; provided,
                  however, that SDS at its sole option may fund an additional
                  $1,000,000 at any time after the Initial Closing Date and
                  prior to March 30, 2002. Upon the mutual agreement of the
                  parties, the Second Closing may occur prior to the Second
                  Closing Date. Each Closing under this Agreement shall take
                  place at the offices of Jenkens & Gilchrist Parker Chapin LLP,
                  The Chrysler Building, 405 Lexington Avenue, New York, New
                  York 10174 at 1:00 p.m. (eastern time) upon the satisfaction
                  of each of the conditions set forth in Section 4 hereof (each,
                  a "Closing Date").

2.       Representations, Warranties and Covenants of the Purchasers. Each of
         the Purchasers, severally but not jointly, represents and warrants to
         the Company, and covenants for the benefit of the Company, as follows:

         2.1.     Each of the Purchasers is an entity duly organized, valid
                  existing and in good standing under the laws of the
                  jurisdiction identified on Exhibit A.

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<PAGE>

         2.2.     This Agreement has been duly authorized, validly executed and
                  delivered by each of the Purchasers and is a valid and binding
                  agreement and obligation of each of the Purchasers enforceable
                  against each of the Purchasers in accordance with its terms,
                  subject to limitations on enforcement by general principles of
                  equity and by bankruptcy or other laws affecting the
                  enforcement of creditors' rights generally, and each of the
                  Purchasers has full power and authority to execute and deliver
                  this Agreement and the other agreements and documents
                  contemplated hereby and to perform its obligations hereunder
                  and thereunder.

         2.3.     Each of the Purchasers has received and carefully reviewed
                  copies of the Public Documents (as hereinafter defined). Each
                  of the Purchasers understands that no Federal, state, local or
                  foreign governmental body or regulatory authority has made any
                  finding or determination relating to the fairness of an
                  investment in any of the Shares and that no Federal, state,
                  local or foreign governmental body or regulatory authority has
                  recommended or endorsed, or will recommend or endorse, any
                  investment in any of the Shares. Each of the Purchasers, in
                  making the decision to purchase the Preferred Shares and the
                  Warrants, has relied upon independent investigation made by it
                  and has not relied on any information or representations made
                  by third parties.

         2.4.     The Purchasers agree that they will not enter into any Short
                  Sales (as hereinafter defined) from the period commencing on
                  the Initial Closing Date and ending on the date which all of
                  the Preferred Shares have been converted and all of the
                  Warrants have been exercised and such Conversion Shares and
                  Warrant Shares are covered by the Registration Statement (as
                  defined in the Registration Rights Agreement). For purposes of
                  this Section 2(d), a "Short Sale" by a Purchaser shall mean a
                  sale of Common Stock by a Purchaser that is marked as a short
                  sale and that is made at a time when there is no equivalent
                  offsetting long position in Common Stock held by such
                  Purchaser. For purposes of determining whether there is an
                  equivalent offsetting long position in Common Stock held by a
                  Purchaser, Conversion Shares that have not yet been converted
                  upon conversion of the Preferred Shares and Warrant Shares
                  that have not yet been issued upon exercise of the Warrants
                  shall be deemed to be held long by such Purchaser, and the
                  amount of shares of Common Stock held in a long position shall
                  be the number of Conversion Shares issuable upon conversion of
                  the Preferred Shares assuming such holder converted all the
                  outstanding principal amount of the Preferred Shares on such
                  date and with respect to Warrant Shares, the number of Warrant
                  Shares issuable upon exercise of the Warrants assuming such
                  holder exercised all of the Warrants on such date.

3.       Representations, Warranties and Covenants of the Company.
         The Company represents and warrants to the Purchasers, and covenants
         for the benefit of the Purchasers, as follows:

         3.1.     The Company has been duly incorporated and is validly existing
                  and in good standing under the laws of the state of Delaware,
                  with full corporate power and authority to own, lease and
                  operate its properties and to conduct its business as
                  currently conducted, and is duly registered and qualified to
                  conduct its business and is in good


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                  standing in each jurisdiction or place where the nature of its
                  properties or the conduct of its business requires such
                  registration or qualification, except where the failure to
                  register or qualify would not have a Material Adverse Effect.
                  For purposes of this agreement, "Material Adverse Effect"
                  shall mean any effect on the business, prospects, operations,
                  properties or financial condition of the Company that is
                  material and adverse to the Company and its subsidiaries,
                  taken as a whole and/or any condition, circumstance, or
                  situation that would prohibit the Company from entering into
                  and performing any of its obligations under this Agreement in
                  any material respect.

         3.2.     The Company has furnished the Purchasers with copies of the
                  Company's most recent Annual Report on Form 10-KSB, as
                  amended, for fiscal year ended December 31, 2000 (the "Form
                  10-K") filed with the Securities and Exchange Commission (the
                  "Commission") and its Quarterly Report on Form 10-Q for the
                  quarterly period ended September 30, 2001 (the "Form 10-Q";
                  collectively with the Form 10-K, the "Public Documents"). The
                  Public Documents and the Commission Documents at the time of
                  their filing did not include any untrue statement of a
                  material fact or omit to state any material fact necessary in
                  order to make the statements contained therein, in light of
                  the circumstances under which they were made, not misleading.
                  As used herein, "Commission Documents" means all reports,
                  schedules, forms, statements and other documents filed by the
                  Company with the Securities and Exchange Commission (the
                  "Commission") pursuant to the reporting requirements of the
                  Securities Exchange Act of 1934, as amended (the " Exchange
                  Act"), including material filed pursuant to Section 13(a) or
                  15(d) of the Exchange Act and the Registration Statement (as
                  defined below) and the Prospectus Supplement (as defined
                  below).

         3.3.     The Shares to be issued by the Company to the Purchasers have
                  been registered under the Securities Act, pursuant to a
                  registration statement on Form S-3, Commission File Number
                  333-64750 (the "Registration Statement") and the Company has
                  filed a prospectus supplement to the Registration Statement
                  (the "Prospectus Supplement") in connection with the
                  transaction contemplated by this Agreement. So long as the
                  Preferred Shares remain outstanding, the Company will maintain
                  the effectiveness of the Registration Statement.

         3.4.     The Company at all times shall remain a reporting company
                  pursuant to the Exchange Act.

         3.5.     The Certificate of Designation and the Shares have been duly
                  authorized by all necessary corporate action and, upon
                  conversion in accordance with the terms of the Certificate of
                  Designation, and upon payment of the exercise price in
                  accordance with the terms of the Warrants, the shares of
                  Common Stock issuable upon conversion of the Preferred Shares
                  or exercise of the Warrants shall be validly issued and
                  outstanding, fully paid and non-assessable.

         3.6.     This Agreement has been duly authorized, validly executed and
                  delivered on behalf of the Company and is a valid and binding
                  agreement and obligation of the Company




                                      -4-
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                  enforceable against the Company in accordance with its terms,
                  subject to limitations on enforcement by general principles of
                  equity and by bankruptcy or other laws affecting the
                  enforcement of creditors' rights generally, and the Company
                  has full power and authority to execute and deliver this
                  Agreement and the other agreements and documents contemplated
                  hereby and to perform its obligations hereunder and
                  thereunder.

         3.7.     The execution, delivery and performance of this Agreement and
                  the Certificate of Designation, the issuance of any of the
                  Shares and the consummation of the transactions contemplated
                  by this Agreement and the Certificate of Designation by the
                  Company, will not (i) conflict with or result in a breach of
                  or a default under any of the terms or provisions of, (A) the
                  Company's certificate of incorporation or by-laws, or (B) of
                  any material provision of any indenture, mortgage, deed of
                  trust or other material agreement or instrument to which the
                  Company is a party or by which it or any of its material
                  properties or assets is bound, (ii) result in a violation of
                  any material provision of any law, statute, rule, regulation,
                  or any existing applicable decree, judgment or order by any
                  court, Federal or state regulatory body, administrative
                  agency, or other governmental body having jurisdiction over
                  the Company, or any of its material properties or assets or
                  (iii) result in the creation or imposition of any material
                  lien, charge or encumbrance upon any material property or
                  assets of the Company or any of its subsidiaries pursuant to
                  the terms of any agreement or instrument to which any of them
                  is a party or by which any of them may be bound or to which
                  any of their property or any of them is subject except in the
                  case of clauses (i)(B) or (iii) for any such conflicts,
                  breaches, or defaults or any liens, charges, or encumbrances
                  which would not have a Material Adverse Effect.

         3.8.     No consent, approval or authorization of or designation,
                  declaration or filing with any governmental authority on the
                  part of the Company is required in connection with the valid
                  execution and delivery of this Agreement or the offer, sale or
                  issuance of the Shares or the consummation of any other
                  transaction contemplated by this Agreement (other than any
                  filings which may be required to be made by the Company with
                  the Commission, or Nasdaq or pursuant to any state or "blue
                  sky" securities laws subsequent to the Closing).

         3.9.     There is no action, suit, claim or proceeding before or by any
                  court or governmental agency or body, domestic or foreign, now
                  pending against or affecting the Company, or any of its
                  properties, which questions the validity of this Agreement or
                  the transactions contemplated thereby or any action taken or
                  to be take pursuant thereto. There is no action, suit, claim
                  or proceeding before or by any court or governmental agency or
                  body, domestic or foreign, now pending against or affecting
                  the Company, or any of its properties, which, if adversely
                  determined, is reasonably likely to result in a Material
                  Adverse Effect.

         3.10.    Subsequent to the dates as of which information is given in
                  the Public Documents, except as contemplated herein, the
                  Company has not incurred any material liabilities or material
                  obligations, direct or contingent, or entered into any
                  material transactions not in the ordinary course of business.


                                      -5-
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         3.11.    The Company has sufficient title and ownership of all
                  trademarks, service marks, trade names, copyrights, patents,
                  trade secrets and other proprietary rights ("Intellectual
                  Property") necessary for its business as now conducted and as
                  proposed to be conducted as described in the Public Documents
                  or the Commission Documents except for any of the foregoing,
                  the absence of which would not reasonably be likely to result
                  in a Material Adverse Effect and, to its knowledge without any
                  conflict with or infringement of the rights of others. Except
                  as set forth in the Public Documents or the Commission
                  Documents, there are no material outstanding options, licenses
                  or agreements of any kind relating to the Intellectual
                  Property, nor is the Company bound by or party to any material
                  options, licenses or agreements of any kind with respect to
                  the Intellectual Property of any other person or entity,
                  except for that certain security interest in and to all of the
                  Company's patents, copyrights and trademarks granted to
                  Hewlett-Packard Company on or about June 25, 1999 and renewed
                  on or about April 9, 2001.

         3.12.    The Company has complied and will comply with all applicable
                  federal and state securities laws in connection with the
                  offer, issuance and sale of the Shares hereunder. The Company
                  will continue to take all action necessary to continue the
                  listing or trading of its Common Stock on the Nasdaq National
                  Market or any relevant market or system, if applicable, and
                  will comply in all material respects with the Company's
                  reporting, listing (including, without limitation, the listing
                  of the Conversion Shares issuable to the Purchasers upon
                  conversion of the Preferred Shares) or other obligations under
                  the rules of the Nasdaq National Market or any relevant market
                  or system. The Company shall comply with all applicable laws,
                  rules, regulations and orders.

         3.13.    The Company will promptly notify the Purchasers of (a) its
                  receipt of notice of the issuance by the Commission of any
                  stop order or other suspension of the effectiveness of the
                  Registration Statement and (b) its becoming aware of the
                  happening of any event as a result of which the prospectus
                  included in the Registration Statement includes an untrue
                  statement of a material fact or omits to state a material fact
                  required to be stated therein, or which makes it necessary to
                  change the Registration Statement in order to make the
                  statements therein, in light of the circumstances under which
                  they were made, not misleading.

         3.14.    Neither this Agreement or the Schedules hereto contain any
                  untrue statement of a material fact or omit to state a
                  material fact necessary in order to make the statements made
                  herein or therein, in the light of the circumstances under
                  which they were made herein or therein, not misleading.

         3.15.    The authorized capital stock of the Company and the shares
                  thereof issued and outstanding as of December 16, 2001 are set
                  forth on Schedule 3(o) attached hereto. All of the outstanding
                  shares of the Company's Common Stock have been duly and
                  validly authorized, and are fully paid and non-assessable.
                  Except as set forth in this Agreement, the Public Documents,
                  the Commission Documents or on Schedule 3(o) attached hereto,
                  as of December 16, 2001, no shares of Common Stock are
                  entitled to preemptive rights or registration rights and there
                  are no


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                  outstanding options, warrants, scrip, rights to subscribe to,
                  call or commitments of any character whatsoever relating to,
                  or securities or rights convertible into, any shares of
                  capital stock of the Company. Furthermore, except as set forth
                  in this Agreement, in the Public Documents, the Commission
                  Documents or on Schedule 3(o) as of the date hereof, there are
                  no contracts, commitments, understandings, or arrangements by
                  which the Company is or may become bound to issue additional
                  shares of the capital stock of the Company or options,
                  securities or rights convertible into shares of capital stock
                  of the Company. Except as disclosed in the Commission
                  Documents and except for customary transfer restrictions
                  contained in agreements entered into by the Company in order
                  to sell restricted securities, as of the date hereof, the
                  Company is not a party to any agreement granting registration
                  rights to any person with respect to any of its equity or debt
                  securities. The Company is not a party to, and it has no
                  knowledge of, any agreement restricting the voting or transfer
                  of any shares of the capital stock of the Company. The offer
                  and sale of all capital stock, convertible securities, rights,
                  warrants, or options of the Company issued prior to the
                  Closing complied with all applicable federal and state
                  securities laws, and no stockholder has a right of rescission
                  or damages with respect thereto which is reasonably likely to
                  have a Material Adverse Effect. The Company has furnished or
                  made available to the Purchasers true and correct copies of
                  the Company's Certificate of Incorporation as in effect on the
                  date hereof (the "Certificate"), and the Company's Bylaws as
                  in effect on the date hereof (the "Bylaws").

         3.16.    The Company will comply in all material respects with the
                  Company's reporting, filing and other obligations under the
                  bylaws or rules of the Nasdaq National Market or any relevant
                  market or system.

         3.17.    The Company shall not issue any press release or otherwise
                  make any public statement or announcement with respect to this
                  Agreement or the transactions contemplated hereby or the
                  existence of this Agreement without the prior written consent
                  of the Purchasers, which shall not be unreasonably withheld.
                  Notwithstanding the foregoing, in the event the Company is
                  required by law or regulation to issue a press release or
                  otherwise make a public statement or announcement with respect
                  to this Agreement or the transaction contemplated hereby prior
                  to or after the Closing, the Company shall consult with the
                  Purchasers on the form and substance of such press release or
                  other disclosure.

         3.18.    The proceeds from the sale of the Preferred Shares and the
                  Warrant Shares will be used by the Company for working capital
                  purposes and shall not be used to repay any outstanding
                  indebtedness or any loans to officer, director, affiliate or
                  insider of the Company.

         3.19.    During the period commencing on the Closing Date and ending on
                  the second (2nd) anniversary thereof, the Company covenants
                  and agrees to promptly notify (in no event later than five (5)
                  days after making or receiving an applicable offer) in writing
                  (a "Rights Notice") the Purchasers of the terms and conditions
                  of any proposed Subsequent Financing. For the purposes hereof,
                  "Subsequent Financing" shall mean a subsequent offer or sale
                  to, or exchange with (or other type of distribution to), any




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                  third party, of Common Stock or any securities convertible,
                  exercisable or exchangeable into Common Stock, including debt
                  securities. The Rights Notice shall describe, in reasonable
                  detail, the proposed Subsequent Financing, the proposed
                  closing date of the Subsequent Financing, which shall be
                  within sixty (60) calendar days from the date of the Rights
                  Notice, including, without limitation, all of the terms and
                  conditions thereof. The Rights Notice shall provide each
                  Purchaser an option (the "Rights Option ") during the thirty
                  (30) trading days following delivery of the Rights Notice (the
                  "Option Period") to inform the Company whether the Purchasers
                  will purchase all or part of the securities being offered up
                  to such Purchaser's pro rata portion of the Purchase Price in
                  such Subsequent Financing on the same, absolute terms and
                  conditions as contemplated by such Subsequent Financing (the
                  "First Refusal Rights"). Delivery of any Rights Notice
                  constitutes a representation and warranty by the Company that
                  there are no other material terms and conditions,
                  arrangements, agreements or otherwise except for those
                  disclosed in the Rights Notice, to provide additional
                  compensation to any party participating in any proposed
                  Subsequent Financing, including, but not limited to,
                  additional compensation based on changes in the purchase price
                  or any type of reset or adjustment of a purchase or conversion
                  price or to issue additional securities at any time after the
                  closing date of a Subsequent Financing. If the Company does
                  not receive notice of exercise of the Rights Option from any
                  of the Purchasers within the Option Period, the Company shall
                  have the right to close the Subsequent Financing on the
                  scheduled closing date with a third party; provided that all
                  of the terms and conditions of the closing are the same as
                  those provided to the Purchasers in the Rights Notice. If the
                  closing of the proposed Subsequent Financing does not occur
                  within ten (10) business days of the scheduled closing date,
                  any closing of the contemplated Subsequent Financing or any
                  other Subsequent Financing shall be subject to all of the
                  provisions of this Section 3(s), including, without
                  limitation, the delivery of a new Rights Notice. The
                  provisions of this Section 3(s) shall not apply to issuances
                  of financing securities in connection with strategic
                  partnerships, licensing of the Company's functionality under
                  strategic license agreements, employee and consultant stock
                  options, acquisition candidates, fees paid to an investment
                  banker and public secondary offerings.

         3.20.    During the period commencing on the Initial Closing Date and
                  ending on the first (1st) anniversary of the Initial Closing
                  Date, if the Company enters into any Subsequent Financing on
                  terms more favorable than the terms governing the Preferred
                  Shares, then the Purchasers in their sole discretion may
                  exchange the Preferred Shares for the securities issued or to
                  be issued in the Subsequent Financing. The Company covenants
                  and agrees to promptly notify in writing the Purchasers of the
                  terms and conditions of any such proposed Subsequent
                  Financing.

         3.21.    The Company covenants and agrees to undertake a formal process
                  under the guidance and advice of H.C. Wainwright & Co., Inc.
                  to explore strategic transactions for the Company.

4.       Conditions Precedent. The obligations hereunder of both the Company and
         the Purchasers to enter into this Agreement and sell and purchase the
         Preferred Shares and the Warrants is subject to their satisfaction or
         waiver, at or before the Closing, of each of the conditions set forth
         below. These conditions are for the Company's and the


                                      -8-
<PAGE>

         Purchasers' sole benefit respectively, and they may waive their own
         rights at any time in their sole discretion.

         4.1.     The parties shall have executed and delivered this Agreement.

         4.2.     The Company shall file the Certificate of Designation
                  designating the Preferred Stock with the Secretary of State of
                  the State of Delaware and shall have delivered a certified
                  copy of the Certificate of Designation to the Purchasers.

         4.3.     The Registration Statement continues to be effective.

         4.4.     Prior to each Closing, the Company shall have filed a
                  prospectus supplement to the Registration Statement with
                  regard to the Shares issued at each Closing.

         4.5.     The Company shall have delivered certificates evidencing the
                  Preferred Shares and the Warrants to the Purchasers.

         4.6.     Upon receipt of the certificates evidencing the Preferred
                  Shares, the Purchasers shall have delivered to the Company
                  immediately available funds as payment in full of the Purchase
                  Price for the Preferred Shares and the Warrants.

         4.7.     Each of the representations and warranties of the Company and
                  the Purchasers shall be true and correct in all material
                  respects as of each Closing Date, except for representations
                  and warranties that speak as of a particular date, which shall
                  be true and correct in all material respects as of such date.

         4.8.     The Company shall have performed, satisfied and complied in
                  all respects with all covenants, agreements and conditions
                  required by this Agreement to be performed, satisfied or
                  complied with by the Company at or prior to each Closing Date.

         4.9.     Trading in the Company's Common Stock shall not have been
                  suspended by the Commission (except for any suspension of
                  trading of limited duration agreed to by the Company, which
                  suspension shall be terminated prior to the Closing), and, at
                  any time prior to the Closing Date, trading in securities
                  generally as reported by Bloomberg Financial Markets
                  ("Bloomberg") shall not have been suspended or limited, or
                  minimum prices shall not have been established on securities
                  whose trades are reported by Bloomberg, or on the New York
                  Stock Exchange, nor shall a banking moratorium have been
                  declared either by the United States or New York State
                  authorities, nor shall the Company have suffered a Material
                  Adverse Effect.


                                      -9-
<PAGE>

         4.10.    At each Closing, the Purchasers shall have received an opinion
                  of counsel to the Company, dated the date of such Closing, in
                  the form of Exhibit E hereto and such other certificates and
                  documents as the Purchasers or its counsel shall reasonably
                  require incident to such Closing.

         4.11.    As of the Initial Closing Date, the Company shall have
                  reserved out of its authorized and unissued Common Stock,
                  solely for the purpose of effecting the conversion of the
                  Preferred Shares and exercise of the Warrants, a number of
                  shares of Common Stock equal to at least 200% of the aggregate
                  number of Shares issuable upon conversion of the Preferred
                  Shares and exercise of the Warrants on the Initial Closing
                  Date.

         4.12.    As a condition only to the Second Closing, the average of the
                  five (5) lowest volume weighted average prices of the Common
                  Stock during the fifteen (15) trading days immediately prior
                  to the Second Closing Date must equal or exceed $.12.

         4.13.    The Company shall have delivered to the Purchasers a
                  secretary's certificate, dated as of each Closing Date, as to
                  (i) the Resolutions, (ii) the Certificate, (iii) the Bylaws,
                  each as in effect at the Closing, and (iv) the authority and
                  incumbency of the officers of the Company executing the
                  Transaction Documents and any other documents required to be
                  executed or delivered in connection therewith.

         4.14.    All fees and expenses required to be paid by the Company shall
                  have been or authorized to be paid by the Company as of the
                  Closing Date.

         4.15.    On the Second Closing Date, the Company shall have delivered
                  to the Purchasers a certificate of an executive officer of the
                  Company, dated as of the Second Closing Date, confirming the
                  accuracy of the Company's representations, warranties and
                  covenants as of the Initial Closing Date and confirming the
                  compliance by the Company with the conditions precedent set
                  forth in this Section 4 as of the Second Closing Date.

5.       Fees and Expenses. The Company and each Purchaser shall pay its
         respective fees and expenses related to the transactions contemplated
         by this Agreement; except that the Company shall pay on the Closing
         Date, all reasonable fees and expenses, exclusive of disbursements and
         out-of-pocket expenses, incurred by the Purchasers of up to $30,000 in
         connection with the preparation, negotiation, execution and delivery of
         this Agreement, the Certificate of Designation and the Warrants.


                                      -10-
<PAGE>

6.       Indemnification.

         6.1.     The Company will indemnify and hold harmless the Purchasers,
                  each of their directors, fund managers and officers, and each
                  person, if any, who controls the Purchasers within the meaning
                  of Section 15 of the Securities Act, or Section 20(a) of the
                  Exchange Act, from and against any third party claims against
                  such Purchasers or persons identified above that result in
                  losses, claims, damages, liabilities and expenses (including
                  reasonable costs of defense and investigation and all
                  reasonable attorneys' fees) to which the Purchasers, each of
                  their directors, fund managers and officers, and each person,
                  if any, who controls the Purchasers may become subject, under
                  the Securities Act or otherwise, insofar as such losses,
                  claims, damages, liabilities and expenses (or actions in
                  respect thereof) arise out of or are based upon, (i) any
                  untrue statement or alleged untrue statement of a material
                  fact contained, or incorporated by reference, in the
                  Registration Statement relating to the Common Stock being sold
                  to the Purchasers (including any Prospectus Supplement filed
                  in connection with the transactions contemplated hereunder
                  which are a part of it), or any amendment or supplement to it,
                  or (ii) the omission or alleged omission to state in that
                  Registration Statement or any document incorporated by
                  reference in the Registration Statement, a material fact
                  required to be stated therein or necessary to make the
                  statements therein not misleading, provided that the Company
                  shall not be liable under this Section 6(a) to the extent that
                  a court of competent jurisdiction shall have determined by a
                  final judgment (with no appeals available) that such loss,
                  claim, damage, liability or action resulted directly from any
                  such acts or failures to act, undertaken or omitted to be
                  taken by the Purchasers or such person through its bad faith
                  or willful misconduct; provided, however, that the foregoing
                  indemnity shall not apply to any loss, claim, damage,
                  liability or expense to the extent, but only to the extent,
                  arising out of or based upon any untrue statement or alleged
                  untrue statement or omission or alleged omission made in
                  reliance upon and in conformity with written information
                  furnished to the Company by the Purchasers expressly for use
                  in the Registration Statement, any preliminary prospectus or
                  the prospectus (or any amendment or supplement thereto); and
                  provided, further, that with respect to the prospectus, the
                  foregoing indemnity shall not inure to the benefit of the
                  Purchasers or any such person from whom the person asserting
                  any loss, claim, damage, liability or expense purchased Common
                  Stock, if copies of the prospectus were timely delivered to
                  the Purchasers pursuant hereto and a copy of the prospectus
                  (as then amended or supplemented if the Company shall have
                  furnished any amendments or supplements thereto) was not sent
                  or given by or on behalf of the Purchasers or any such person
                  to such person, if required by law so to have been delivered,
                  at or prior to the written confirmation of the sale of the
                  Common Stock to such person, and if the prospectus (as so
                  amended or supplemented) would have cured the defect giving
                  rise to such loss, claim, damage, liability or expense.

         6.2.     The Company will reimburse the Purchasers and each such
                  controlling person promptly upon demand for any legal or other
                  costs or expenses reasonably incurred by the Purchasers or any
                  controlling person in investigating, defending against, or
                  preparing to defend against any such claim, action, suit or
                  proceeding, except that the Company will not be liable to the
                  extent a claim or action which results in a loss, claim,
                  damage, liability or expense arises out of, or is based upon,
                  an untrue statement, alleged untrue statement, omission or
                  alleged omission, included in any Registration Statement,
                  prospectus or Prospectus Supplement or any amendment or
                  supplement to the thereto in reliance upon, and in conformity
                  with, written information


                                      -11-
<PAGE>

                  furnished by the Purchasers to the Company for inclusion in
                  the Registration Statement, prospectus or Prospectus
                  Supplement.

7.       Indemnification Procedures. Promptly after a person receives notice of
         a claim or the commencement of an action for which the person intends
         to seek indemnification under Section 6, the person will notify the
         indemnifying party in writing of the claim or commencement of the
         action, suit or proceeding, but failure to notify the indemnifying
         party will not relieve the indemnifying party from liability under
         Section 6, except to the extent such indemnifying party has been
         materially prejudiced by the failure to give notice. The indemnifying
         party will be entitled to participate in the defense of any claim,
         action, suit or proceeding as to which indemnification is being sought,
         and if the indemnifying party acknowledges in writing the obligation to
         indemnify the party against whom the claim or action is brought, the
         indemnifying party may (but will not be required to) assume the defense
         against the claim, action, suit or proceeding with counsel satisfactory
         to it. After an indemnifying party notifies an indemnified party that
         the indemnifying party wishes to assume the defense of a claim, action,
         suit or proceeding the indemnifying party will not be liable for any
         legal or other expenses incurred by the indemnified party in connection
         with the defense against the claim, action, suit or proceeding except
         that if, in the opinion of counsel to the indemnifying party, one or
         more of the indemnified parties should be separately represented in
         connection with a claim, action, suit or proceeding the indemnifying
         party will pay the reasonable fees and expenses of one separate counsel
         for the indemnified parties. Each indemnified party, as a condition to
         receiving indemnification as provided in Section 6, will cooperate in
         all reasonable respects with the indemnifying party in the defense of
         any action or claim as to which indemnification is sought. No
         indemnifying party will be liable for any settlement of any action
         effected without its prior written consent. No indemnifying party will,
         without the prior written consent of the indemnified party, effect any
         settlement of a pending or threatened action with respect to which an
         indemnified party is, or is informed that it may be, made a party and
         for which it would be entitled to indemnification, unless the
         settlement includes an unconditional release of the indemnified party
         from all liability and claims which are the subject matter of the
         pending or threatened action.

         If for any reason the indemnification provided for in this agreement is
not available to, or is not sufficient to hold harmless, an indemnified party in
respect of any loss or liability referred to in Section 6, each indemnifying
party will, in lieu of indemnifying the indemnified party, contribute to the
amount paid or payable by the indemnified party as a result of the loss or
liability, (i) in the proportion which is appropriate to reflect the relative
benefits received by the indemnifying party on the one hand and by the
indemnified party on the other from the sale of stock which is the subject of
the claim, action, suit or proceeding which resulted in the loss or liability or
(ii) if that allocation is not permitted by applicable law, in such proportion
as is appropriate to reflect not only the relative benefits of the sale of
stock, but also the relative fault of the indemnifying party and the indemnified
party with respect to the statements or omissions which are the subject of the
claim, action, suit or proceeding that resulted in the loss or liability, as
well as any other relevant equitable considerations.

8.       Governing Law; Consent to Jurisdiction. This Agreement shall be
         governed by and interpreted in accordance with the laws of the State of
         New York without giving effect to the rules governing the conflicts of
         laws. Each of the parties consents to the exclusive jurisdiction of the
         Federal courts whose districts encompass any part of the County of New
         York located in the City of New York in connection with any dispute
         arising under this


                                      -12-
<PAGE>

         Agreement and hereby waives, to the maximum extent permitted by law,
         any objection, including any objection based on forum non conveniens,
         to the bringing of any such proceeding in such jurisdictions. Each
         party waives its right to a trial by jury. Each party to this Agreement
         irrevocably consents to the service of process in any such proceeding
         by the mailing of copies thereof by registered or certified mail,
         postage prepaid, to such party at its address set forth herein or its
         agent. Nothing herein shall affect the right of any party to serve
         process in any other manner permitted by law.

9.       Notices. All notices and other communications provided for or permitted
         hereunder shall be made in writing by hand delivery, express overnight
         courier, registered first class mail, or telecopier, initially to the
         address set forth below, and thereafter at such other address, notice
         of which is given in accordance with the provisions of this Section.

                           (a)      if to the Company:

                                    The viaLink Company
                                    13155 Noel Road
                                    Suite 700
                                    Dallas, Texas 75240
                                    Attention: Chief Executive Officer and
                                               Chief Financial Officer
                                    Tel. No.: (972) 934-5500
                                    Fax No.:  (972) 934-5583

                           (b)      if to the Purchasers:

                                    At the address of such Purchaser set forth
                                    on Exhibit A with a copy to such Purchaser's
                                    counsel as set forth on Exhibit A:

         All such notices and communications shall be deemed to have been duly
given: when delivered by hand, if personally delivered; when receipt is
acknowledged, if telecopied; or when actually received or refused if sent by
other means.

10.      Entire Agreement. This Agreement constitutes the entire understanding
         and agreement of the parties with respect to the subject matter hereof
         and supersedes all prior and/or contemporaneous oral or written
         proposals or agreements relating thereto all of which are merged
         herein. This Agreement may not be amended or any provision hereof
         waived in whole or in part, except by a written amendment signed by
         both of the parties.

11.      Counterparts. This Agreement may be executed by facsimile signature and
         in counterparts, each of which shall be deemed an original, but all of
         which together shall constitute one and the same instrument.

                                  [end of page]



                                      -13-
<PAGE>





         IN WITNESS WHEREOF, this Agreement was duly executed on the date first
written above.


                                             THE VIALINK COMPANY



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



                                             PURCHASER:



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






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








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




                                      -14-
<PAGE>

                                    EXHIBIT A
              PURCHASERS / NUMBER OF PREFERRED SHARES AND WARRANTS

<Table>
<Caption>
NAMES AND ADDRESSES                      NUMBER OF PREFERRED SHARES    DOLLAR AMOUNT
OF PURCHASERS                            & WARRANTS PURCHASED          OF INVESTMENT
-------------------                      --------------------------    -------------
<S>                                      <C>                           <C>
SDS Merchant Fund, L.P.                  Preferred Shares:             Initial Closing:
c/o SDS Capital Partners                 Initial Closing:              $2,000,000
One Sound Shore Drive                    Second Closing:               Second Closing:
Greenwich, Connecticut 06830             Series A Warrants:            $3,000,000
Attention: Steve Derby                   Series B Warrants:
Fax No.: (203) 629-0345
Jurisdiction: Delaware

With a copy to:

Jenkens & Gilchrist Parker Chapin LLP
The Chrysler Building
405 Lexington Avenue
New York, New York 10174
Attention:  Christopher S. Auguste
Tel. No.: (212) 704-6000
Fax No.: (212) 704-6288

[Name of Purchaser]                      Preferred Shares:              Initial Closing:
                                         Initial Closing:               $
---------------------                    Second Closing:                Second Closing:
                                         Series A Warrants:             $
---------------------
Fax No.: (   )    -
          ---  --- ----
Attention:
Jurisdiction:




[Name of Purchaser]                      Preferred Shares:              Initial Closing:
                                         Initial Closing:               $
---------------------                    Second Closing:                Second Closing:
                                         Series A Warrants:             Third Closing:
---------------------                                                   $
Fax No.: (   )    -
          ---  --- ----
Attention:
Jurisdiction:
</Table>




                                      -15-
<PAGE>



                                    EXHIBIT B
                       FORM OF CERTIFICATE OF DESIGNATION


                                    EXHIBIT C
                            FORM OF SERIES A WARRANT


                                    EXHIBIT D
                            FORM OF SERIES B WARRANT






                                      -16-