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 Calculated (calculated field: A field in which the value is determined by Project based on information in other fields. Project may recalculate the value automatically or when you specify, depending on your choice of calculation settings.)
Description The WBS Predecessors field lists the work breakdown structure (WBS) (WBS: A hierarchical structure that is used to organize tasks for reporting schedules and tracking costs. With Project, you can represent the work breakdown structure by using task IDs or by assigning your own WBS code to each task.) codes associated with the predecessor (predecessor: A task that must start or finish before another task can start or finish.) tasks on which the task depends before it can start or finish. Each predecessor 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 WBS Predecessors field to a task sheet when you want to display a list of the task predecessors. Also use the WBS Predecessors field when sorting, grouping, or filtering by WBS predecessors. Each predecessor task is represented by its WBS code, which may be followed by a link type (link type: The type of task dependency. The four dependency types are Finish-to-start [FS], Finish-to-finish [FF], Start-to-start [SS], and Start-to-finish [SF].) and the lead or lag time. The link types for predecessors are FS (finish-to-start), FF (finish-to-finish), SS (start-to-start), and SF (start-to-finish). Lead time is represented by a negative number, and lag time is represented by a positive number.
Example You use a custom WBS code structure in your project and you want to review the predecessors of tasks in your project to analyze and refine the schedule. You add the WBS Predecessors field to the Task Sheet view. For the "Write proposal" task, the WBS Predecessors field contains the entry "B.15.c[FS+3 days]." This means that the task with the WBS code of B.15.c is a predecessor of this task, with a finish-to-start dependency and a three-day lag time. Before this task can start, it must wait three days after the finish of task B.15.c.
Remarks You can use the Link Tasks command 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 view. You can set other dependency types and any delays to the tasks you want in the Task Information dialog box.
If there is more than one predecessor, 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.), such as the comma or semicolon.
If a predecessor task does not have a WBS code, the field is blank.
If a predecessor is a task in another project, the WBS Predecessors field contains the full path name for the task, along with the WBS code.