1. Geant3 All collaborations are using G3 to a certain extent
All collaborations agree G3 is on its way out
CMS and LHCb pretty much advanced in their move to G4
Atlas running their DCs with G3
Alice still based on G3 but they have an operational interface to G4 (via AliRoot)
concern that a G3.5 might be in the workings

2. Geant4
All collaborations agree that there is no alternative to G4 (not yet, at least)
LHCb and CMS already pretty much based on it, Atlas is late, Alice still support it
All collaborations request that G4 be more (mostly) focussed on the LHC needs
All collaborations request that the physics programme be more targeted at the LHC needs
to be looked at by the HEP-URC?
All collaborations complain b/c of lack of modularity (G4RunManager etc..)

3. Geant4 (cont’d)
All collaborations regret some lack of interactive functionality (being worked around by using home-grown facilities (Iguana, Panoramix, Root…)
All collaboration are trying to dismantle (to different extent) the G4 framework and use it as a real toolkit
Event generation
User “actions”
Physics lists

4. Fluka All collaborations agree that:
it is desirable to have an alternative to G4
the only possible alternative is (as of today) Fluka
Fluka should be supported, maintained, documented and (in general) publicly available
it would be desirable to have a common “Detector simulation suite” that allows one to use either G4 or Fluka as simulation engine by starting from the same geometry, event generator, user actions….

5. Geometrical model
All collaborations have/are developing their own geometrical model, which should be used by different applications (sim, rec, vis)
everybody would like to see “geometry” somehow separated from “tracking”
everybody expressed interest in Rene’s geometrical model as it seems a possible unifying factor
Rene’s model offers lots of facilities which are quite appealing (navigational capabilities, interactivity, etc…)