The critical path in Microsoft Project: reading it correctly
The critical path says which tasks set the finish date. Badly built, it shows the wrong tasks, and you closely watch what does not matter.
critical task available slack
Microsoft Project calculates the critical path on its own: the chain of tasks where the slightest delay pushes back the end of the project. The schedule still has to give it what it needs to calculate correctly.
What slack tells you
Each task has a total slack: the delay it can take without moving the finish date. A task with no slack is critical. In our product launch example, specifications, prototype, testing and industrialization have no slack. Documentation, however, can slip by 5 days with no consequence.
Traps that distort the critical path
- tasks with no successor, which look critical while leading nowhere;
- imposed dates, which break the chain of dependencies;
- missing links, which make a critical task look non-critical.
Watch what matters
An accurate critical path lets you focus attention. In meetings, look first at the tasks with no slack: they decide the date. A task with 5 days of slack can wait until next week.
Check it regularly
The critical path changes as work progresses: a task falling behind can join it. It should be reviewed at every significant schedule update, not only at kick-off. The More With Project virtual coach helps spot the missing links and imposed dates that distort it.