Schedule Constraints are any limitations that affect the start or finish date of a dependent task. They are placed on a schedule of dependent tasks in the form of fixed dates imposed on the tasks. Schedule constraints are bottlenecks that restrict a task from achieving scheduled completion of its goals.
There are three types of schedule constraints, such as:
- Immediate. This type means that a dependent task is scheduled to the earliest possible time it can start at. For example, there is a project schedule that is in progress. Adding a new task to this schedule means placing a respective constraint on the schedule; the task’s start date will be current immediate date but not the start date of the schedule.
- Start on/after target date. It is used in cases when there is a need to restrict a dependent task from start on or after a specified target date. This task will start no earlier than the target date.
- Finish on/before target date. This type of schedule constraints restricts a dependent task from completion on or before a specified target date. The task will finish no later than the target date.