In the process of coordinating and keeping track of all of the different components of a project, the project management team, and specifically the project management team leader, will devise a number of individual schedules, each of which will maintain track of a specific component of element of the project on a smaller, more specified scale. However, keeping track of where things rest on the big picture of the project as a whole can be an arduous process, particularly in light of the number of individual schedules that exist for the various components mentioned above. As a result, it is important if not essential for the project team leader to compile a thorough and complete master schedule for the project. This master schedule represents a summary-level project schedule the purpose of which is to identify all of the major deliverables for the project as well as all individual work breakdown structure components. Also identified typically are all unique schedule milestones. See also milestone schedule.
This term is defined in the 3rd and the 4th edition of the PMBOK.