Data Type Integer List (integer list field: A type of field whose content is a list of whole numbers separated by the list separator character, typically a comma. Examples include the Predecessors and Successors fields.)
Entry Type Entered (entered field: A field in which you may type or edit information. This is in contrast with a calculated field, in which Project calculates and enters information.)
Description The Unique ID Successors field lists the unique ID (unique ID: A unique number that Project automatically assigns to a task, resource, or assignment. It will not change as other tasks or resources are added to or removed from the project.) numbers for the successor (successor: A task that cannot start or finish until another task starts or finishes.) tasks to a task. A task must start or finish before successor tasks can start or finish. Each successor is linked to the task by a specific type of task dependency (task dependencies: A relationship between two linked tasks; linked by a dependency between their finish and start dates. There are four kinds of task dependencies: Finish-to-start [FS], Start-to-start [SS], Finish-to-finish [FF], and Start-to-finish [SF].) and a lead time (lead time: An overlap between tasks that have a dependency. For example, if a task can start when its predecessor is half-finished, you can specify a finish-to-start dependency with a lead time of 50 percent for its successor [has a negative lag value].) or lag time (lag time: A delay between tasks that have a dependency. For example, if you need a two-day delay between the finish of one task and the start of another, you can establish a finish-to-start dependency and specify a two-day lag time [has a positive value].).
Best Uses Add the Unique ID Successors field to a task view when you want to display or update task successors by their unique ID rather than task ID. Each successor is represented by its unique ID number, which may be followed by a dependency and the lead or lag time. The dependency types for successors are FS (finish-to-start), FF (finish-to-finish), SS (start-to-start), and SF (start-to-finish). To enter lead time, type a negative number. To enter lag time, type a positive number.
Example You want to review the successors of tasks in your project to analyze and refine the schedule. You add the Unique ID field and the Unique ID Successors field to the Task Sheet view. In the Unique ID Successors field for the "Develop estimate" task, you see the entry "14FS+3d" meaning that the task with Unique ID14 is a successor of this task, with a finish-to-start dependency, and a 3-day lag time. Before the task with Unique ID14 can start, it must wait 3 days after the finish of this task. You also see that the Unique ID Successors field for the "Conduct client meetings" task is blank. You type "15FS" to link this task to the task with unique ID15 with a finish-to-start dependency.
Remarks If you enter only the task unique ID number in the Unique ID Successors field, Project assumes a finish-to-start dependency with zero lag time. If there is more than one successor, they are all listed and separated by the list-separator character (list-separator character: A character, usually a comma or semicolon, that separates elements in a list.), which is typically the comma.
You can use the Link Tasks command on the Edit menu to link the selected tasks with finish-to-start dependencies and zero lag time. You can also link tasks by dragging from one task to the other on the chart portion of the Gantt Chart or Network Diagram.
If a successor is a task in another project, the Unique ID Successors field also contains the path to the linked project, in addition to the task's Unique ID and dependency type. An example is: C:\My Documents\Bldg E Construction.mpp\3FF.