Critical Path Management (CPM)

Importance of Critical Path Scheduling

When resources are allocated to a project it's the Project Manager’s responsibility for managing those resources efficiently. Creating a critical path schedule enables Project Managers to optimize their resources, so that there is little waste. A CPM schedule is important because it determines the most efficient way to deliver a project.

What is Critical Path

The critical path is the sequence of project tasks that, when added together, will determine how long the project will take to be completed. If any tasks on the critical path slip a week, the project’s end date will slip a week. Project Managers use critical path schedules to analyze which tasks are essential for completing the project in the shortest time possible, and which tasks aren't critical.

Critical Path Definition

A visual task scheduling technique that estimates the shortest duration possible for completing a project.

CPM Schedule Example

The CPM schedule visually illustrates the critical path. The schedule above shows project management teams which tasks are on the critical path. Out of the seven tasks on the schedule, Prototyping and Integration Testing are not on the critical path. The tasks (red) that are on the critical path will determine the end date of the project.

Slack

All projects will have some tasks that are not as time constrained as others. These are the tasks on the schedule that will not jeopardize the project completion date if they are finished a bit later than their planned dates. The time between the soonest date the task can be finished and the latest date it must be finished is called slack.

In the CPM schedule above, the tasks Prototyping and Integration Testing each have a few days of slack because they can push their finish dates back. Prototyping must be completed by July 15 and Integration Testing must be completed July 26 before they impact the end date of the project.

Identifying the Critical Path

The best way for Project Managers to identify the critical path is to create a critical path diagram. This diagram will help identify which tasks are dependent on others before they can begin. It will also illustrate what tasks can happen at the same time. There will be multiple paths to completion, however there will only be one path that will complete the project in the shortest amount of time. In the example above, path 3 is the critical path because it shows the minimum duration for completing all of the project’s tasks.

Project scheduling, planning and management

Projects can get complicated and using visual based tools is helpfull in cutting through complexity. In addition to critical path schedules there a number of visual aids that will help Project Managers deliver and manage projects efficiently.

Executive project schedules

Visual tools like PowerPoint are useful for communicating complex project information in a simple way. Creating diagrams and schedules in graphical way helps clients and executives understand project tasks and their dependencies.

Office Timeline is a PowerPoint project scheduler for creating schedules that clients and executives understand.