Constraints in Primavera P6 are special dates that restricts the start or completion date of activities. If you use a constraint in a schedule, you would set the date of the constraint manually to the date you require, as it is independent of any currently scheduled dates. This can affect the critical path of the schedule, which is why there are concerns about constraint usage; shown in most of the guidelines for good scheduling.
In this video, we will discuss the different types of constraints and common the mistakes made with constraint usage. These can result in a schedule that is impractical, unrealistic, or illogical
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