Offer Document Posted

Serco Group plc

17 December 2004

Not for release, publication or distribution in, into or from the United
States, Canada, Australia or Japan.

                    RECOMMENDED OFFER TO ACQUIRE ITNET PLC                     

                      TO BE MADE BY LAZARD & CO., LIMITED                      

                         ON BEHALF OF SERCO GROUP PLC                          

                           POSTING OF OFFER DOCUMENT                           

Serco Group plc ('Serco') announces today that the Offer Document in relation
to the recommended cash offer with a partial share alternative (the 'Offer')
for ITNET plc ('ITNET') to be made by Lazard & Co., Limited ('Lazard') on
behalf of Serco, to acquire the entire issued and to be issued ordinary share
capital of ITNET, is being posted to ITNET shareholders (other than certain
overseas shareholders) today, together with the Form of Acceptance.

The Offer is open for acceptance until 3.00pm (London time) on 7 January 2005
(unless extended).

To accept the Offer, ITNET shareholders should complete , sign and return the
Form of Acceptance, whether or not ITNET shares are held in CREST, in
accordance with the instructions set out in the Offer Document and in the Form
of Acceptance so as to be received as soon as possible, and, in any event, by
no later than 3 .00 p.m. (London time) on 7 January 2005.

ITNET shareholders who do not receive a copy of the Offer Document or the Form
of Acceptance may obtain copies of either of those documents from the Receiving
Agent, Computershare Investor Services PLC, 2nd Floor, Vinters Place, 68 Upper
Thames Street, London, EC4V 3BJ, during normal business hours.

ENQUIRIES

Serco Group plc                        [phone]                   
                                                                             
Dominic Cheetham, Director of Corporate Communications                       
                                                                             
Richard Hollins, Head of Investor Relations                                  
                                                                             
Lazard & Co., Limited (Financial       [phone]                   
Adviser to Serco)                                                            
                                                                             
Paul Jameson                                                                 
                                                                             
Samuel Bertrand                                                              
                                                                             
Weber Shandwick Square Mile            [phone]                   
                                                                             
Louise Robson                                                                

Terms used in this announcement shall have the same meaning as those in the
Offer Document.

The Offer will not be made, directly or indirectly, in or into, or by use of
the mails or any means of instrumentality (including without limitation
facsimile transmission, telex and telephone) of interstate or foreign commerce
of, or any facilities of a national securities exchange of the United States,
nor will it be made in or into Canada, Australia or Japan. Accordingly, copies
of this announcement are not being, and must not be, mailed or otherwise
distributed or sent in or into or from the United States, Canada, Australia or
Japan and persons receiving this announcement (including custodians, nominees
and trustees) must not distribute or send it in, into or from the United
States, Canada, Australia or Japan.

This announcement does not constitute, or form any part of, any offer for, or
solicitation of any offer for securities. Any acceptance or other response to
the Offer should be made only on the basis of the information contained in the
Offer Document and the Form of Acceptance.