Project Management: Foundations to Practice · Schedule Management and the Critical Path Method
The Critical Path Method
CPM has quietly underpinned schedule discipline since the 1950s. This chapter covers its industrial origin and why identifying the critical path is the single highest-leverage scheduling insight a project manager can generate.
The Critical Path Method, commonly abbreviated CPM, was developed in the late 1950s through work at DuPont and Remington Rand to plan and schedule complex industrial projects, and it remains one of the most widely used scheduling techniques today [16]. It emerged from a genuinely practical, industrial need: managing the complexity of plant construction and maintenance shutdowns where thousands of interdependent activities needed to be coordinated with minimal wasted downtime.
- CPM was developed in the late 1950s at DuPont and Remington Rand to manage complex industrial scheduling.
- The critical path is the longest duration sequence of dependent activities through the network, not the one with the most activities.
- Non-critical activities have float (slack) and can slip without affecting the project's finish date; critical path activities cannot.
- Identifying the critical path lets a project manager concentrate limited monitoring attention where it actually protects the deadline.