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Critical Path Method

A powerful tool for managing complex problems

The Critical Path Method helps visualize complex projects and displays which activities are critical to completing the project and which are not.

Created in the 1950s, the Critical Path Method helps planners anticipate and monitor the essential activities of a project. This not only helps you set realistic schedules, but also identifies which steps should be accelerated to meet deadlines.

01

Identify all activities in your project’s plan. List the earliest start date and estimated amount of time to complete that activity.

Identify activities

02

Next, determine the sequence of the activities. Note which activities cannot be started until certain other preceding activities have been completed.

03

Plot these activities on separate notes/writing surfaces using circle and arrow diagrams.

a.Circles show events within the project.
b.Arrows between two circles show the activity needed to complete the event. Write a description of the task underneath the arrow and the estimated length of time need to complete the task above the arrow.

Plot activities

04

Build each of these activities into your timeline. In some cases, your timeline might be a straight line or may branch off in multiple directions — it all depends on your project.

05

Now you can identify the critical path. Simply look for the longest-duration path through your diagram — these are the activities that cannot be delayed without delaying your project.

identify the critical path

06

As your project progresses, update your critical path with actual event completion times to get a more accurate plan. Changes in the plan caused by unforeseen circumstances or other factors may also create a new critical path for your project.

Find the products that bring this method to life at post-it.com/collaborate