shows the situation is getting worse, not by a little bit, but by a lot. This might be a sign of what Deming refers to as "special cause variation." Certainly, it is worth further investigation, and possibly action.

By the third week, the situation is beginning to improve. The project buffer is no longer being penetrated while the project's critical chain is progressing.

By week 4, the situation is much better. Due to one or more tasks on the Critical Chain finishing earlier than expected, the project has gotten some of its safety back. The project buffer is only 15 percent consumed, as the Critical Chain completion percentage grows.

Note that any task on the Critical Chain that is completed earlier than expected adds that amount of safety back to the project buffer. Any task on a feeding path that finishes earlier than expected adds that amount of safety to the feeding buffer. This assumes that the next resource on the path is flexible enough to take advantage of an early finish from a previous task.

As reinforced by the case studies, buffer management is key to the success of any Critical Chain implementation. Senior managers who have implemented Critical Chain also advise that buffer status should rigidly dictate priorities. From a project manager's perspective, the first priority is the task currently penetrating the project buffer. The next priority is the task or tasks penetrating the feeding buffer(s).

For organizations with critical milestones, where either bonuses or penalties depend on meeting them, the second priority is another buffer, called the "milestone" buffer. It behaves almost identically to the project buffer. In effect, the milestone buffer protects a subset of the project. That subset is like a mini-project. In this case, the milestone buffer is a subset of the overall project buffer, and is used to monitor and give early warning to a milestone date that may be at risk.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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