Identification and illumination of popular misconceptions about project scheduling and time buffering in a resource-constrained environment

The lack of proper project planning is often cited as one of the main reasons why projects fail to be completed in time and within budget. In this paper, we identify and illuminate several possible misconceptions that go round in project management periodicals and in the mindset of practising project managers and that may hamper successful project planning. The misconceptions relate to the role of the critical path, the critical sequence (critical chain), active schedules, and the insertion of buffers in the baseline schedule as a protective mechanism against schedule distortions during project execution. The possible fallacies are illustrated using example schedules developed for an illustrative project.

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