The Program Evaluation and Review Technique (PERT) is a widely used method for planning and coordinating large-scale projects. As Harold Kerzner explained in his book Project Management, “PERT ...

Program Evaluation and Review Technique (PERT) ... Identify the longest path in the PERT diagram. This is the critical path because it sets time constraints on the whole project.

H.B. Zachry Co., San Antonio, developed a form of CPM called precedence diagramming method, which is widely used today in place of the old activity-on-arrow diagramming method.