HKSM
Critical Chain Method (CCM)
A scheduling technique that explicitly considers resource limits and inserts buffers to protect delivery dates.
Key Points
- Builds the critical chain by accounting for both task dependencies and resource constraints.
- Uses a project buffer at the end of the critical chain and feeding buffers where noncritical paths join it.
- Discourages multitasking and relies on realistic, focused task durations.
- Monitors buffer consumption to control schedule risk and guide corrective actions.
Example
A software release plan shows several teams sharing one database specialist. After identifying the critical chain that reflects this resource dependency, the manager places a project buffer at the end of the chain and feeding buffers where other streams flow into it. As work progresses, the team tracks buffer usage to decide when to add help or re-sequence tasks.
PMP Example Question
Which scheduling approach creates a resource-constrained critical path and adds buffers to protect the final delivery date?
- Critical Path Method (CPM)
- Resource leveling
- Critical Chain Method (CCM)
- Monte Carlo simulation
Correct Answer: C — Critical Chain Method (resource-constrained scheduling with buffers)
Explanation: CCM explicitly considers resource limits and adds project and feeding buffers to protect the schedule, unlike CPM or standalone resource leveling.
