A guide to the Critical Path method

Critical Path Overview

Project managers are expected to hit the ground running, being responsible for their own and the project teams’ work. Understanding the Critical Path Method is a vital step towards successfully planning and scheduling the tasks of the team.

The CPM (Critical Path Method) is a mathematical approach to scheduling a set of project activities. It enables you to assess task priority, the resources required and possible shortcuts to project completion.

CPM is based on the creation of a sequence of dependent tasks (IE. tasks that can only be performed after earlier tasks are complete). Performing an analysis on this sequence allows you to work out possible parallel sequences (IE. tasks that can be performed simultaneously).

What is a Critical Path?

The Critical Path is the longest chain of dependent tasks required to successfully complete the project. A tool for the creation of a Critical Path is an MS Project Gantt chart that provides a visual representation of task dependencies, task priorities and the interaction of critical paths across multiple projects.

How to apply the Critical Path technique to your project.

Specify the individual tasks necessary for project success
Determine sequences of tasks
Draw a network diagram
Identify the critical path (the longest chain of dependent tasks)
Estimate completion time (work out how long each task will take and by adding the time for each task in the longest chain, I can work out the project duration)
Update for progress (a vital element to ensure the project remains viable is to update your estimates with actuals and see the knock-on affect on future estimates)

What does the Critical Path do?

The Critical Path Method enables you to work out the most efficient task route, task priorities and the most effective ways of shortening project duration.

By identifying which tasks / activities lie on the Critical Path and then monitoring their progress, the project manager can help to deliver the project on time. Any delays to these critical tasks will delay the project completion. This is why the Critical Path Method remains one of the most important tools for any project manager.