Critical Path
The chain of activities that makes up the longest route through the schedule; its total duration sets the minimum time needed to finish the project.
Key Points
- Activities on the critical path have zero total float; any delay on them delays the project finish.
- There can be more than one critical path at the same time, which increases schedule risk.
- The critical path can change as estimates, logic, or actual progress are updated; recalculate it regularly.
- To shorten the overall timeline, focus on critical-path work using crashing or fast tracking.
Example
A project has two paths: A-B-C totaling 30 days and D-E totaling 18 days. A-B-C is the critical path. If task B slips by 2 days, the whole project finish slips by 2 days unless you compress B or another activity on the critical path.
PMP Example Question
Which statement best defines the critical path in a project schedule?
- The path with the largest number of activities.
- The sequence of activities with zero total float whose total duration sets the earliest possible project completion.
- The set of activities with the highest costs.
- The path containing tasks with the most risk responses.
Correct Answer: B - The longest-duration path with zero float that sets the minimum project duration
Explanation: Only the longest path with zero total float determines the earliest achievable finish date; other paths have float and do not control project completion.
HKSM