Predecessors (task field) - Project - Office.com

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Predecessors (task field)

Data Type     Integer List

Entry Type     Entered

Description     The Predecessors field lists the task ID numbers for the predecessor tasks on which the task depends before it can be started or finished. 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 Predecessors field to a task view when you want to display or update task predecessors. Each predecessor task is represented by its task ID number, which may be followed by a dependency type and the lead or lag time. The dependency types for predecessors 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 predecessors of tasks in your project to analyze and refine the schedule. In the Task Sheet view, the Predecessors field contains the entry "14FS+3d" for the "Write proposal" task. This means that task 14 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 14. The Predecessors field for the "Conduct client meetings" task is blank. You type "15FS" to link this task to task 15 with a finish-to-start dependency.

Remarks     If you enter only the task ID number in the Predecessors field, Project assumes a finish-to-start dependency with zero lag time. If there is more than one predecessor, they are all listed and separated by the list-separator character, which is typically the comma or semicolon.

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. You can set other dependency types in the Task Information dialog box.

If a predecessor is a task in another project, the Predecessors field also contains the path to the linked project, in addition to the task ID and dependency type. An example is: C:\My Documents\Bldg_E_Construction.mpp\3FF.