Critical Path Method

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What Does Critical Path Method Mean?

The critical path method (CPM) is a step-by-step methodology, technique or algorithm for planning projects that have complex, interdependent interactions. Technically, the critical path will have the least amount of float. In project management, float is defined as the amount of time a task can be delayed without causing a delay to subsequent tasks.


An important goal of CPM is to help stakeholders understand which tasks should be carried out in which order. In supply chain planning, CPM software features are often used to identify potential bottlenecks and predict their corresponding work-arounds. In computer networking, CPM software can be used to optimize network performance and improve quality of service (QoS).

Techopedia Explains Critical Path Method

CPM is an important tool for project management because it helps project managers and stakeholders separate critical tasks from non-critical tasks.

It plays an important role in helping project managers understand which missed milestones could prevent the entire project from being successfully completed on time — as well as where extra resources could help.

How Do you Find A Project's Critical Path?

The basic steps employed in CPM are:

  1. Determine required tasks.
  2. List required tasks in sequence.
  3. Create a flowchart including each required task.
  4. Identify all critical and non-critical relationships (paths) among required tasks.
  5. Assign an expected completion/execution time for each required task.
  6. Study all critical relationships to determine possible alternatives for as many as possible.

CPM Use Cases

CPM is commonly employed in many diverse types of projects, including product development, engineering, construction, aerospace and defense, software development and research projects.

Often a major objective in CPM is to figure out how to complete a project in the shortest time possible. When the critical path depicts the longest path through a project, this information can be used to determine the shortest possible time it would take to complete a project.

One way to optimize completion time is called fast tracking, which involves performing activities in parallel (simultaneously) and adding resources to shorten critical path durations (called crashing the critical path). Left unchecked, this may also result in expansion and inadvertently lead to increasing project complexity, duration or both.

Several CPM software solutions are available for tracking critical paths and most project planning software vendors include CPM features in their products.


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Margaret Rouse
Technology Expert
Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.