As the project plan is first built, tasks are typically inserted and deleted frequently. The result is a project plan that is numbered inconsistently. As a general rule, it is a good idea to renumber tasks in the order in which they are located in the WBS, so the numbering scheme is maintained in the parent-child task relationships. It is acceptable to renumber your project plan as often as needed in the project planning phase, typically before the project is baselined.

Once the project is baselined, Team Members may start using task numbers as reference identifiers.

Upon clicking on the Renumber command, the Renumber Tasks dialog box will be displayed enabling users to renumber a project’s tasks.