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                                                                   EXHIBIT 10.13


                               ALLIANCE AGREEMENT

     This Alliance Agreement ("Agreement"), dated as of June 21, 1999, is by
and between PETROCHEMNET HOLDINGS, INC., a Delaware corporation
("PetroChemNet"), and DEWITT & COMPANY INCORPORATED, a newly-formed Texas
corporation ("DeWitt").

                                    RECITALS

     This Agreement outlines our mutual objectives in entering into an ongoing
Strategic Alliance between the parties hereto, following the anticipated
reorganizations transactions consummated on or about the date hereof involving
PetroChemNet, DeWitt, the stockholders of DeWitt and certain other parties. As a
result of those reorganizations transactions, among other things, PetroChemNet
acquired CheMatch, Inc., a Texas corporation ("CheMatch"). The purposes of this
Agreement include fostering the growth and development of PetroChemNet and
DeWitt, among others.

     FOR GOOD AND VALUABLE CONSIDERATION, the receipt and sufficiency of which
are hereby acknowledged:

1.   DeWitt will place its products on a DeWitt branded channel on the
     PetroChemNet Information Platform, directly accessible at
     "dewitt.petrochem.net" to provide analysis, information and consulting
     services on an appropriate fee sharing basis.

2.   DeWitt will provide Trading Analysis and Support on the PetroChemNet
     Trading Platform (formerly CheMatch). These services will be provided on a
     fee sharing basis with the anticipation that the share to PetroChemNet will
     be significantly lower than for items presented on the Information
     Platform.

3.   PetroChemNet will develop a Tier One Level of service for the exclusive
     purpose of providing DeWitt's Trading Analysis and Support directly to
     Trading Platform users, subject to a first right of refusal provision as
     defined below. Tier One Level will be defined as the only level from which
     actual data and/or commentary can be accessed directly (one toggle away)
     from the actual Trading Platform screen.

4.   Both DeWitt and PetroChemNet acknowledge that PetroChemNet will provide
     other links from the sales and trading platform on a Tier Two basis to its
     own information and analysis, and to other information, analysis and
     services as may be useful to the value of the sales and trading activity.
     Tier Two basis shall mean that a menu screen describing other data and/or
     commentary available will be accessible from the trading screen but not the
     actual data and/or commentary screen itself.

5.   Tier One exclusivity for Dewitt will be subject to a first right of
     refusal. For those product areas included or planned for inclusion on a
     Trading Platform which are not yet covered by a DeWitt Consulting Service,
     DeWitt will be granted a right of first refusal to broaden its consulting
     line to match new PetroChemNet product additions. DeWitt agrees to develop
     such products and services at its expense. Both parties agree to provide
     reasonable notice in relation to their interactions in this area.

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6.   PetroChemNet will grant Dewitt access to trading information and screens
     (in preference to other consulting companies only) for product areas for
     which DeWitt provides online information. PetroChemNet retains the right to
     offer such trading pricing and other information from Trading Platform
     activities to third parties that are not competitors of Dewitt.

7.   DeWitt agrees to use reasonable commercial efforts to assist in the
     promotion of membership participation, liquidity, and usage of the
     PetroChemNet Trading Platform. To this end DeWitt will allow its client
     lists to be used via offering CheMatch trading to all clients of the
     appropriate associated DeWitt Services.

8.   Dewitt retains the right to offer or deliver its Consulting Services via
     other alternative marketing and/or delivery modes as may best fit its
     business objectives. DeWitt will not offer Trading Services for specific
     products on another competitive Trading Platform as long as those products
     are being significantly traded on PetroChemNet.

9.   All DeWitt Consulting Services and the new Trading Services provided by
     DeWitt on the Trading Platforms and the content thereof remain the express
     property of Dewitt and may not be sold or distributed in any manner other
     than outlined in this Agreement.

10.  Both parties recognize that there will be costs involved in bringing DeWitt
     products and services into the PetroChem.net system. Both agree that costs
     to develop, produce, and market DeWitt's basic Services will be
     undertaken by the parties to reflect reasonable burden sharing related to
     making the products and services available over the PetroChem.net system.
     For the new Trading Analysis and Support services, PetroChemNet will share
     a reasonable burden for staff as it relates to the ongoing input and screen
     maintenance for the Trading platform.

11.  PetroChemNet may terminate this Agreement upon the payment to DeWitt of
     $500,000 in cash. DeWitt may terminate this Agreement with or without cause
     on one year's prior written notice upon the payment to PetroChemNet of
     $60,000 at such final termination date. Upon any such termination, all
     rights and obligations under this Agreement shall terminate and be of no
     further force or effect.

12.  In the event that either party (the "Non-Defaulting Party") believes that
     the other party hereto has failed to perform any of its obligations under
     this Agreement or if a dispute arises between the parties hereto involving
     the subject matter of this Agreement, the Non-Defaulting Party may provide
     notice of such failure or a notice of such dispute to the other party and
     both parties agree to promptly meet and attempt to resolve that failure to
     perform or dispute in an amicable manner, before any action is brought by
     either party hereto in any court of competent jurisdiction regarding that
     matter.

13.  Each of Teresa A. Acosta, Earl H. Armstrong and William P. Barry (the
     "Stockholders") join in the execution and delivery of this agreement
     exclusively for the purposes of this Section, and no others. None of them
     shall be personally liable for any action or omission of DeWitt under this
     Agreement except as provided in this Section. As additional consideration
     for PetroChemNet's entering into this




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Agreement, neither any Stockholder nor DeWitt shall, during the term of this
Agreement, directly or indirectly, for himself, herself or itself or on behalf
of or in conjunction with any other person, persons, company, partnership,
corporation or business of whatever nature, supply for use on any Internet-based
trading platform (a "Trading Platform") any daily trading analysis ("Daily
Product Information") relating to any petrochemical or petrochemical-based
product. Notwithstanding the foregoing, if a Stockholder and/or DeWitt in good
faith wish, at any time during the term of this Agreement, to supply Daily
Product Information for use on a Trading Platform with respect to any
petrochemical or petrochemical-related product that neither PetroChemNet nor any
of its affiliates (including CheMatch Inc., a Texas corporation, PetroChemNet,
Inc., a Delaware corporation, and any of their respective successors or assigns
(including any subsequent direct or indirect purchaser of the CheMatch On-Line
system), all of whom, collectively with PetroChemNet, are sometimes referred to
herein as a "PetroChemNet-related Party") is not then offering on a Trading
Platform, then such party (a "Supplying Party") shall first provide to
PetroChemNet written notice (the "Offer Notice") of the Supplying Party's wish
to do the same, which Offer Notice shall set out the petrochemical or
petrochemical-related product with respect to which the Supplying Party wishes
to provide such information, and if the following provisions are complied with
by that Supplying Party, it shall not be deemed a breach of the provisions set
out above in this Section. The Supplying Party agrees that, during the 90-day
period after delivery of an Offer Notice, it will not offer the Daily Product
Information that was the subject of such Offer Notice to any party for use on a
Trading Platform. During such 90-day period, the Holdings-related Parties shall
have an exclusive right to determine whether or not they want to have the
Supplying Party supply such Daily Product Information for use on the
Holdings-related Parties' Trading Platform, which right will include an
exclusive right in favor of the Holdings-related Parties to negotiate with the
Supplying Party as to the terms thereof during that 90-day period. If an
agreement is not reached between the Supplying Party and the relevant
Holdings-related Party during that 90-day period, then the Supplying Party shall
be free to engage in supplying such Daily Product Information to or for the
benefit of any party, and the Holdings-related Parties shall be free to acquire
such Daily Product Information from any other source or to develop such Daily
Product Information itself, in any case, on any terms and conditions each such
party deems acceptable in its sole and absolute discretion, which terms may be
similar or dissimilar to those discussed by it with the other related party.
Notwithstanding any provision of this Section or any other agreement to the
contrary, including without limitation any provision of (including without
limitation the indemnity provisions set out in Section 9 of) that certain
Agreement and Plan of Reorganization, by and among the parties hereto, Fred B.
Cook, PetroChemNet, Inc., a Delaware corporation, and a wholly-owned subsidiary
of PetroChemNet which was merged into PetroChemNet, Inc., no Stockholder shall
be personally liable for a breach of the covenants set out in this Section, nor
shall he or she be obligated for any indemnity or contribution for a breach of
the covenants set out in this Section, unless that Stockholder either alone or
with any other person, persons, company, partnership, corporation or business of
whatever nature, engaged (whether for himself or herself or on behalf of any
such other person or party, and whether directly or indirectly) in the activity
that first resulted in that breach of such covenants.

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         In general, PetroChemNet and DeWitt agree to explore and develop other
joint business opportunities and relationships in other areas that are mutually
agreed and beneficial. PetroChemNet and DeWitt anticipate that following the
acquisition of CheMatch, PetroChemNet will, for a brief interim period, maintain
appropriate office space in DeWitt's Office Suite in Houston for the purpose of
sales, account management and customer support. Accordingly, DeWitt and
PetroChemNet will enter into a Service Agreement and work jointly toward shared
personnel and support facilities as appropriate. This approach should offer
efficiencies and cost savings. Not withstanding this, PetroChemNet may, locate
its facilities as it may, in its sole discretion, after reasonable notice is
given.

Accepted and Agreed:




DEWITT & COMPANY INCORPORATED                PETROCHEMNET HOLDINGS, INC.


By: /s/ EARL H. ARMSTRONG                    By: /s/ JOHN A. BOHN, JR.
   --------------------------------             -------------------------------
   Earl H. Armstrong                            Name: John A. Bohn, Jr.
   As Its Authorized Vice President             As Its Authorized President



TERESA A. ACOSTA                             EARL H. ARMSTRONG


/s/ TERESA A. ACOSTA [BY EARL H. ARMSTRONG]  /s/ EARL H. ARMSTRONG
--------------------                         ---------------------

WILLIAM P. BARRY

/s/ WILLIAM P. BARRY
--------------------