Program Evaluation and Review Technique (PERT) is an important network technique useful in planning and controlling. The main goal of PERT is to reduce the cost and time needed to complete a project. This technique is especially useful for planning; scheduling and implementing time bound projects involving performance of a variety of complex, diverse and interrelated activities. This technique deals with time scheduling and resource allocation for these activities and aims at effective execution of projects within given time schedule and structure of costs.

The steps involved in using PERT are as follows:

  1. The project is divided into a number of clearly identifiable activities which are then arranged in a logical sequence.
  2. A network diagram is prepared to show the sequence of activities, the starting point and the termination point of the project.
  3. Time estimates are prepared for each activity. PERT requires the preparation of three time estimates – optimistic (or shortest time), pessimistic (or longest time) and most likely time.
  4. The longest path in the network is identified as the critical path. It represents the sequence of those activities which are important for timely completion of the project and where no delays can be allowed without delaying the entire project.
  5. If required, the plan is modified so that execution and timely completion of project is under control.

PERT is used extensively in areas like ship-building, construction projects, aircraft manufacture, etc.