Task dependencies, lead, and lag
Lead and lag adjust timing between linked tasks, while cross-project dependencies connect tasks in separate project files. For creating or editing dependency links and reviewing the four link types, see Task Links and Dependency Editing.
When to use lead or lag
Section titled “When to use lead or lag”Lead lets the successor overlap with its predecessor. For a finish-to-start dependency, a -2d lead allows the successor to start up to two working days before the predecessor finishes, subject to other scheduling inputs.
Lag adds waiting time before the successor. For a finish-to-start dependency, a 2d lag requires at least two working days between the predecessor’s finish and the successor’s start. Enter either value in the dependency’s Lag field. Use lead or lag when it represents a real timing relationship, such as overlapping work or a required wait between tasks.1
Cross-project dependencies
Section titled “Cross-project dependencies”Project can display and update task dependencies across projects. Changes to external dependencies do not automatically update the current project’s schedule, so review the reported changes and accept only those that should affect the plan.2
For other scheduling inputs that affect dates, see How Microsoft Project schedules tasks, Calendars in Microsoft Project, and Resources in Microsoft Project.