We are planning to form a Forum to enhance the communication between Geant4 users and developers regarding requirements, results and feedback. At the last Geant4 TSB and CB meetings we agreed to hold 'prototype' meetings of this proposed "Geant4 Technical Forum" during the second half of 2003, in order to start putting into practice this emerging new structure and communication mechanism.

The rough idea of the 'Technical Forum' is to bring together the users with Geant4 developers, to focus on new requirements in physics, functionality and/or usability of the G4 toolkit, enhance the structured exchange of information, and to promote the creation of prioritized requirements for future developments.

Since Geant4's users are geographically dispersed, it will be necessary to hold the meetings in different locations, and eventually to enable off-site video or telephone connection.

For the first meeting we will use the opportunity of the Geant4 Collaboration Meeting at Vancouver, Canada on September 2nd-6th, taking advantage of the significant number of Geant4 developers who will be present. Currently a large part of Friday, September 5th is set aside for user presentations, and the organizers have kindly agreed to host the first proto-Technical Forum meeting after these sessions in the late afternoon (Friday September 5th). Please look for details of the exact time and location soon at the Geant4 2003 Workshop web site, URL http://www.triumf.ca/geant4-03

We wish to organize a second meeting of the proto-Technical Forum, to be hosted at CERN in October 2003. The proposed date for this second meeting is Tuesday, October 7th.

For these meetings, I would like to solicit your input, regarding
- new or important requirements,
- technical issues regarding the use of Geant4,
- the usability of the toolkit,
- the current support process,
and encourage your participation.

Makoto Asai is organizing the first meeting at Vancouver, so please contact him at in order to propose an item for its agenda.

As these will be the first meetings of this 'proto'-body, it will be important to attempt to be flexible in organizing, learning and adapting them to the needs of the Users and to enable the best communication with the Collaboration. I look forward to your participation, and your feedback regarding these first meetings.

Please forward this message to your colleagues and most-active Geant4 users. We plan to promote subsequent meetings more widely, with announcements in further appropriate mailing lists.

Best regards,

John Apostolakis
Makoto Asai