As you go through the project, one of the important actions that you take is to set up status meetings for the project team. In these meetings, you look at the project baseline and discuss the project's status, or in other words, how well you have kept to the original plan. You will have a Schedule and a WBS at a very minimum. Even if you don't create formal plans for other areas (which will happen in some cases, particularly in fairly short projects), you must have a Schedule and a WBS to manage a project.
For many organizations, it seems that meetings take the place of working. Don't let this happen on your projects. First, you should write down and formalize who is going to attend the status meetings. This simple information is part of the communication plan. Who should go to the meetings? That depends on who needs information to get the project done. On long projects, there may be people who won't be involved at the beginning of the project but who will do important tasks later. There is no, I repeat, no good reason to ask those people to be at the early status meetings. You can talk to them by phone, keep them up to date, email them, but they do not need to sit in meetings where the discussion doesn't directly affect them. If their tasks begin five months from now, you shouldn't demand that they sit through early status meetings unless they actually want to do so. If they find it helpful to be there, people will ask to be informed about when your status meetings are held. If they find it painfully boring to sit through status meetings that give them no useful information for their particular part of the project, you will see their eyes glaze over during your meetings.