The primary difference between appointments and meetings is in the way they are managed. Appointments flow more or less according to the whims of the more powerful person—generally less affected by the purpose of the meeting. Meetings are supposed to be run according to an agenda. Before discussing agendas, let's quickly go over something common between meetings and appointments—maintenance. Meetings, too, may be moved or cancelled. It is important to communicate such changes to all invitees so that they do not unnecessarily end up attending a meeting that no longer exists or go to the wrong place or attend at the wrong time. In fact, good communication is very critical to effective meeting management.