Over the course of a given project, often times, it is up to the project management team and or the project management team leader to make a determination that the previously determined and derived schedule may need to be modified and or tweaked in one way or another in order to accommodate one of more schedule events. This may be because a particular event is running behind schedule, or in other cases because a succeeding event’s timing has to e changed one way or another. However, it is important to understand and keep in mind that changes cannot be made in a haphazard and reckless manner. Careful tabs must be kept on all of them to assure that control is maintained by those in charge, such as the project management team and or the project management team leader. The actual process of maintaining control of the changes that may occur to a schedule is in fact known as schedule control.
This term is defined in the 3rd edition of the PMBOK but not in the 4th.