Description:

This is one of the first papers that defined Resource Critical Path, Resource Constrained Activity and Assignment Floats and Success Driven Project Management methodology. RCP and SDPM are compared with Critical Chain definition and methodology.

Resource critical path is a true critical path in projects with resource constraints. If project resources are unlimited RCP is equivalent to the traditional critical path. Activity floats shall be calculated considering all schedule constraints. Only resource constrained floats can be used for project control because they show the real activity time reserves. Assignment floats are the tools that are even more powerful in project control. They show resource time reserves that may be used for project resource management.

When the Critical Chain is correctly defined it may appear that it is the same as the RCP. Both the RCP and the Critical Chain recommend to use optimistic estimates of activity duration and contingency and management buffers for project control. RCP approach offers to calculate contingency reserves by simulating project risks. Project risk simulation allows to simulate not only uncertainties of activity duration and cost data but also all possible risk events. The most probable and pessimistic schedules may include activities and resources that are lacking in the optimistic schedule.

These theories differ in their conclusions. Thus, we believe that:

• RCP can change during the project execution
• multitasking is sometimes necessary, and
• critical resources can be different at the different stages of project life cycle.