What is PERT? | Definition, Uses, Component and Pros

PERT stands for Program Evaluation and Review Technique. It initially stood for Program Evaluation Research Task, but was renamed after 1959. It is a statistical tool that was used to analyze and understand the steps in finishing any project. Thus, it belongs to the domain of project management.

In 1958 it was created and developed by the United States Navy for the Polaris nuclear submarine project. PERT was especially useful in determining the time required to complete specific tasks, as well as the fastest and slowest possible pace for the same.

It was very useful to the Navy in situations where time was of the essence, and saving time was more important than avoiding or estimating costs. Over time it found applications in large scale, complex projects and bigger development projects.

The Use of PERT

  1. This can be used in projects in which the goals and steps are clearly laid out. Even if that is not properly demarcated, the time estimated usually reflects the ideal case scenario.
  2. It is a very practical technique as it factors in the uncertainties in any given project.
  3. It can be fairly simplified for purposes of comprehension. The tool requires diagrams with nodes and arrows to be drawn up, in which the arrows are indicative of the next steps and the nodes represent the finished portions of the project.
  4. Aside from project management, PERT can also be used in corporate or education sectors. Here efficiency can be increased by quite a few times by feeding the available information and planning ahead to save time and cost of production.

Components of PERT

  1. The Event is the point of the diagram that refers to the starting or point of completion of one or more tasks. This point of the diagram can be reached in practical use only when all the steps leading to it are complete.
  2. The Predecessor is any event that comes right before another, without any other interconnected steps involved.
  3. The Successor is any event that follows another, without any steps in between.
  4. PERT activity refers to the real activity or the performance that requires the variables of time, labour, and resources for completion.
  5. PERT also makes allowances for sub-activities which are the smaller steps involved in a bigger event.

Aside from this there are several provisions made for the progression of time and its calculation.

Advantages of PERT

  1. It enables a better understanding and cost effective planning of any project by clearly highlighting the steps involved.
  2. It facilitates better decision making by diagrammatically representing the problems faced till completion.
  3. The interrelationships between cost, labour, and time can be clearly understood.

Disadvantages of PERT

  1. It is difficult to determine an exact singular plan of action when bigger projects are involved.
  2. If the networks become too interconnected and complex, the diagram becomes sprawling and messy and difficult to interpret.
  3. There are several subjective factors involved in any project and this makes the whole process uncertain and inaccurate.


  1. https://ascelibrary.org/doi/abs/10.1061/(ASCE)0733-9364(1999)125:1(16)
  2. https://europepmc.org/article/med/10141769
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