Critical path and dependencies

The critical path is the chain with no slack. Knowing which tasks are on it tells you which delays matter and which genuinely do not.

The idea

In any plan with dependencies, one chain of tasks determines the end date. That is the critical path, and it has zero slack: any delay on it moves the finish.

Everything off it has float. A task with five days of float can slip four and change nothing, which is why treating every delay as equally urgent wastes attention.

Critical path and dependencies, in three chapters

Why it matters most with a fixed date

When the date cannot move, float is the only resource you have. Knowing where it is tells you where to push and where to leave people alone.

Without it, a two-day supplier delay produces either panic or indifference, and which one you get depends on who noticed rather than on whether it mattered.

Read next

Critical path and dependencies, answered.

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