As an environment, PCIS2 must take care of users. They should be able to login/logout, and to get their environment as they left it previously. As PCIS2 is distributed, one user may not always be on the same machine, so we need to take care about itinerant or mobile environment. Also considered is the fact that one machine may have a different OS and/or a dif-ferent set of tools. So, in order to manage this situation, we must be able to track both the machine environment and the user's preferences.