Often when you manage several projects, some of them may be related, with the start and finish dates of tasks in one project depending on the start and finish dates of tasks in another. For example, if the inserted projects in a consolidated file represent project phases, perhaps the first task of one phase can’t begin until the last task of the preceding phase ends.
Projects within a consolidated file aren’t the only ones that can have dependencies. There can be dependencies between two or more stand-alone projects. For instance, you might want to ensure that a resource assigned to tasks in two different projects wouldn’t have to work on both projects at the same time. You’d want to make sure that one task didn’t start until the other is finished.
To show dependencies between projects in the same consolidated project file or between different project files, you can link tasks between projects. The links between projects work the same way as links do between tasks within the same project.
By default, the following procedure establishes a finish-to-start dependency between tasks. After you’ve linked the tasks, however, you can change the link to a start-to-start, finish-to-finish, or start-to-finish link. (You can also specify lead and lag time.) For information about linking tasks, see Chapter 5, "Getting Tasks Done in the Right Order, at the Right Time."
To link tasks between projects
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You can link tasks between individual (unconsolidated) projects by typing "project name\ID" in the predecessor field (where project name is the file name of the project containing the task you want to link to and ID is the ID of the task you want to link to).
If the start or finish date of an entire project is dependent on the start or finish date of another entire project, and not just of a task within the project, you can link one project to another.
To link two projects
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