Step 4: Schedule Development involves the development of realistic start and finish dates for each activity. An iterative process, schedule development takes into account activity sequencing, duration estimates, resource requirements and availability, calendars that show when work can be performed, constraints, assumptions, and risk. 
The output of this step is a set of schedules for the program. These include the master program schedule and the supporting detailed schedules, which should reflect the best balance possible between competing demands of time and resources. They should also take into account the risk associated with time, cost, and performance tradeoffs and the impact on the overall program.
A number of techniques and tools are useful in developing schedules, many of which are contained in various scheduling software applications. Many of these applications contain the capability to perform various types of mathematical analyses to calculate theoretical start and finish dates for each activity based on the overall sequencing of the program activities. Two (2) of the more commonly known analysis techniques are: 
Other scheduling development techniques that are commonly used focus on schedule development in light of resource (time, people, funds, material) constraints. These techniques provide the means to manage the effect of these constraints. A few of these techniques are: 
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