Activity Relationship

When scheduling a project, the activity relationship is defined to ensure that the activities are sequenced accurately to provide realistic start and end dates. An activity relationship is a logical relationship indicating that an activity (successor) cannot start or end until the preceding activity starts or ends. The predecessor or successor activity can also be a milestone activity. A predecessor task cannot be linked twice to the same successor task. You cannot create, edit or delete a relationship for projects with Finished, Closed or Archived status.

Using activity relationship

You can use the Activity Relationships (tppss2510m000) session to define the activity relationship between the activities of a project. In the session, you can also specify the data such as the plan, activities (successor and predecessor), relationship type and cost type of the activities. The relationship type of the activities can have these values:

  • Finish-to-Start: The task initiation of the successor activity is based on the task completion of the predecessor activity.
  • Finish-to-Finish: The task completion of the successor activity is based on the task completion of the predecessor activity.
  • Start-to-Start: The task initiation of the successor activity is based on the task initiation of the predecessor activity.
  • Start-to-Finish: The task completion of the successor activity is based on the task initiation of the predecessor activity.

Lead time is the overlap between the activities with a dependency. You must specify the lead time as a negative value.

Lag time is a delay between the activities with a dependency. You must specify the lag time as a positive value.

You can specify the lead and lag in unit of time or percentage.