The communication between the team members (team members from both – my implementing company and the client) is a crutial part of the project. There may be 2 ways of dealing with it: individual contact or email-groups.
The advantage of email-groups approach is that every member of the particular group (suggested groups could be management/ IT management/ implementation/ development where development group includes implementation members and implementation group includes IT management) is being informed about the actual status and pending issues/questions.
The email-groups can also help with dealing with member-relations, because there is usually someone else involved in the communication (even as a silent partner). If there is a need to deal with a situation (technical or personal) then there is no need for using CC: or even BCC: that may offend some team members.
The disadvantage may be that there is a lot of communication (emails) going back and forth, because there are always multiple members included. However it gives a chance to different members to react on the questions or tasks (and gives a great deal of overview to the IT management)…
Did anyone make an experience with this approach that would prove it being an issue creator? Did you experienced rules on whom to include in each group and how to define them?