HKSM

A notable marker or event in a project, program, or portfolio that indicates progress, completion of a phase, or a key decision point.

Key Points

• By convention, a milestone has zero duration and consumes no resources.
• Marks phase completions, major deliverables, approvals, or go/no-go decisions.
• Included in the schedule baseline and often shown as a diamond on Gantt charts for status reporting.
• Achievement is confirmed by clear acceptance criteria and can trigger dependencies or contractual payments.

Example

At the end of the design phase, the team targets the "Design Approved" milestone. Once the steering committee signs off on the design package, the milestone is achieved, development work can start, and a milestone payment is released per the contract.

PMP Example Question

Which statement best describes a milestone in a project schedule?

1. An activity that requires resources and has a defined duration
2. A zero-duration marker that indicates a significant event or decision point
3. A detailed work package at the lowest level of the WBS
4. A technique used to sequence activities based on resource availability

Correct Answer: B — A zero-duration marker indicating a significant event or decision point

Explanation: A milestone represents a noteworthy point in the schedule, not work to be performed. It is not a work package or a sequencing technique.