WBS Predecessors (task field)

Data Type     Integer List

Entry Type     Calculated

Description     The WBS Predecessors field lists the work breakdown structure (WBS) codes associated with the predecessor 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 and a lead time or lag time.

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 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, 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.