Abstract
Precedence diagram method includes four types of dependencies, which are Finish to start, Finish to finish, Start to start and Start to finish as logical relationship. In PMBOK, the predecessor (successor) activity is defined as an activity to come before (after) a dependent activity in a schedule. Based on this definition, four types of dependencies in PMBOK are explained definitely logically. However, logical relationship and time relationship do not accord in Start to finish relation. Therefore, in this presentation, author replaces logical relationship of activities with time relationship and priority of activities and then considers a description of four types of dependencies in the precedence diagram method.
