Master Projects and Subprojects
A master project brings separate MPP files together into one overall plan. The inserted files are called subprojects: they appear in the master task list, while their schedules can remain in their own files. This structure is useful when teams need to manage project components separately but coordinate their sequence and overall progress.1
When to use a master project
Section titled “When to use a master project”Use a master project when a large or distributed effort has components that need separate ownership, but leaders still need a consolidated view. Subprojects can be expanded to inspect their task detail or collapsed to keep the overall outline manageable. For a smaller plan that one person can maintain, a single project file is usually simpler.
If the goal is only to compare, report on, or print several files together, a temporary consolidation or a workspace may be a better fit than linking subprojects. These options bring files together for review without making them a master/subproject hierarchy.1
Insert a subproject
Section titled “Insert a subproject”In desktop Project, open or create the master plan and choose View > Gantt Chart. Select the row where the subproject should appear, then choose Project > Subproject. Select the project file and decide whether to leave Link to project selected before inserting it.2
- With Link to project selected, the master and source file stay connected. Changes to the linked project can flow between the files when the link is updated; review and accept external updates rather than assuming dependent schedules recalculate automatically.
- Clear Link to project when you want an independent copy in the master plan. Later edits in the master will not update the original source file.
- For a linked subproject that should not be edited from the master, choose Insert Read-Only. Direct changes to the source file can still appear in the master.
In the master task list, a subproject appears like a summary row with a Project indicator. Expand it to inspect its task outline. The subproject’s underlying information can be edited from the master when it was not inserted read-only; the subproject row itself is not an ordinary summary task. For the behavior of regular summary tasks and subtasks, see the outline guide.
Dependencies and resources across files
Section titled “Dependencies and resources across files”Tasks in different project files can be connected with external dependencies, but Project does not automatically recalculate a dependent project’s schedule when an external task changes. Review and accept external-link updates periodically, including when Project prompts you, then check how the update affects the schedule.3
Project Plan 365 also supports master projects and subprojects; its Drive 365 provides product-specific cloud storage, sharing, and permission controls.
Keep the project hierarchy useful
Section titled “Keep the project hierarchy useful”The master/subproject structure describes how project files relate; it does not replace the task dependencies that determine scheduling order. Use task links and dependencies when one project’s work must wait for another project’s work, and review the critical path when you need to understand which sequence controls the overall finish.