Milestone triggers

Use milestone triggers to take an action close to a target date. For example, if a project deadline cannot be met, use a milestone trigger to automatically alert (email) the project manager who can address the issue by assigning more resources to the project or adjusting the due date.

You can define milestone triggers for a process to be executed before or after the milestone due date is reached, or define it to be executed when the milestone due date is met.

See Create a milestone trigger.