Filed pursuant to Rule 425
                                                    Filing company: Genesys S.A.
                                             Subject company: Vialog Corporation
                                               Commission File Number: 333-55392



                               Vialog Acquisition:
        The Board of Directors of Genesys SA decides that the dilution of
                     its shareholding will not exceed 26.5%



Montpellier, France - March 8, 2001 - The Board of Directors of Genesys SA met
at 10:00 a.m. on March 8, 2001 to consider the potential dilution that could
result from the acquisition of Vialog Corporation (AMEX : VX) under the terms of
the merger agreement signed in October 2000.

The merger agreement provides that, in determining the share exchange ratio, if
the weighted average Genesys share price* during a 10 trading day determination
period is less than or equal to USD 33.6356 (approximately C 36), the exchange
ratio will remain fixed at 0.6703 Genesys ADSs for each Vialog share, resulting
in a maximum potential dilution of approximately 26.5 %. If the average Genesys
price is below this level, the Board of Vialog will have the right to terminate
the merger agreement by notice to Genesys two trading days before Vialog's
shareholder meeting.

Taking into account the information available to it, current market conditions
and the financial results recently published by the two companies, the Board of
Genesys determined that the maximum dilution rate of 26.5% represents an
equitable exchange ratio, reflecting the respective contributions of the two
companies to the new group. The Board believes that this exchange ratio is also
in the interest of the shareholders of Genesys.

As a result, the Board of Genesys has decided, based on current conditions, not
to exercise its right to adjust the exchange ratio if the Board of Vialog were
to decide to exercise its right to terminate the merger agreement. The exchange
ratio will thus under current conditions be fixed as set forth above, at a
maximum of 0.6703 ADSs for each Vialog share, resulting in a maximum dilution
rate of 26.5 %.

The capital increase relating to the Vialog acquisition will be submitted for
approval by the shareholders of Genesys on March 23, 2001. The shareholders
meeting of Vialog has also been called for March 23, 2001.

The Board of Genesys reaffirms its recommendation in favor of the acquisition of
Vialog and confirms the strategic interest of this alliance.


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* The volume-weighted average of the closing prices of the parent shares on the
Nouveau Marche of the 10 consecutive trading days ending on the second trading
day prior to the day of the Special Meeting.


About Genesys Conferencing:
Founded en 1986, Genesys Conferencing is the world's leading independent
conferencing specialist : audio conference, data conference, video conference
and webstreaming. Working in a rapidly growing market and enjoying unique
world-wide coverage as a result of its geographic expansion policy, Genesys
Conferencing has established its advanced technology in 16 countries throughout
Europe, Asia Pacific and the United States. Genesys Conferecing is listed on the
Nouveau Marche in Paris (Euroclear code: 3955).


GENESYS CONFERENCING
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Marine BRUN                                 Florence CATEL
Shareholder and Investor Relations          Press Relations
Tel : + 33 4 67 06 75 17                    Tel : + 33 4 67 06 27 49
investor@genesys.com                        florence.catel@genesys.com

US SEC Filings
Genesys has filed a registration statement on Form F-4 (No. 333-55392) with the
United States Securities and Exchange Commission. The Form F-4 contains a proxy
statement / prospectus relating to the Vialog special meeting and other related
documents. Vialog plans to mail the proxy statement/prospectus contained in the
Form F-4 to its stockholders. The Form F-4 and proxy statement/prospectus
contain important information about Genesys, Vialog, the Vialog transaction and
related matters. Investors and stockholders should read the proxy
statement/prospectus and the other documents filed with the US SEC in connection
with the Vialog transaction carefully before they make any decision with respect
to the Vialog transaction. A copy of the merger agreement with respect to the
Vialog transaction has been filed by Vialog as an exhibit to its Form 8-K dated
October 2, 2000. The Form F-4, the proxy statement/prospectus, the Form 8-K and
all other documents filed with the US SEC in connection with the transaction are
available free of charge at the US SEC's web site at www.sec.gov. In addition,
the proxy statement/prospectus, the Form 8-K and all other documents filed with
the US SEC in connection with the Vialog transaction will be made available to
investors free of charge by calling or writing to:

Genesys S.A.
Pierre Schwich
Chief Financial Officer
4 Rue Jules Ferry, BP 1145
34008 Montpellier, Cedex 1, France
Phone: 33 4 67 06 27 55
Email: pierre.schwich@genesys.com


Vialog Corporation
Michael E. Savage
Chief Financial Officer
32 Crosby Drive
Bedford, MA 01730
Phone: 781-761-6200
Email: msavage@vialog.com

In addition to the Form F-4, the proxy statement/prospectus and the other
documents filed with the US SEC in connection with the Vialog transaction,
Vialog is obligated to file annual, quarterly and special reports, proxy
statements and other information with the US SEC. You may read and copy any
reports, statements and other information filed with the US SEC at the US SEC's
public reference rooms at 450 Fifth Street, N.W., Washington, D.C. 20549 or at
the other public reference rooms in New York, New York and Chicago, Illinois.
Please call the US SEC at 1-800-SEC-0330 for further information on public
reference rooms. Filings with the US SEC also are available to the public from
commercial document-retrieval services and at the web site maintained by the US
SEC at http//www.sec.gov.


Forward-Looking Statements
This release contains statements that constitute forward looking statements
within the meaning of the U.S. Private Securities Litigation Reform Act of 1995.
Forward looking statements are statements other than historical information or
statements of current condition. These statements appear in a number of places
in this release and include statements concerning the parties' intent, belief or
current expectations regarding future events, including: the transactions to
which the parties may be a party; competition in the industry; changing
technology and future demand for products; changes in business strategy or
development plans; ability to attract and retain qualified personnel; worldwide
economic and business conditions; regulatory, legislative and judicial
developments; financing plans; and trends affecting the parties' financial
condition or results of operations. Forward looking statements are not
guarantees of future performance and involve risks and uncertainties, and actual
results may differ materially from those in the forward looking statements as a
result of various factors. Although management of the parties believe that their
expectations reflected in the forward looking statements are reasonable based on
information currently available to them, they cannot assure you that the
expectations will prove to have been correct. Accordingly, you should not place
undue reliance on these forward looking statements. In any event, these
statements speak only as of the date of this release. Except to the extent
required by law, the parties undertake no obligation to revise or update any of
them to reflect events or circumstances after the date of this release, or to
reflect new information or the occurrence of unanticipated events.