Constraint

An item or requirement that will prevent an activity from starting, advancing or completing as planned. Typical constraints on design tasks are inputs from others, clarity of requirements criteria for what is to be produced or provided, approvals or releases, and labor or equipment resources. Typical constraints on construction tasks are the completion of design or prerequisite work; availability of materials, information and directives. Screening tasks for readiness is assessing the status of their constraints. Removing constraints is making a task ready to be assigned.