In one line: Turn the work breakdown into a timeline: give each task a duration, link the tasks by their dependencies, find the critical path, and mark the milestones that tell everyone whether you are on track.
Core idea
A schedule answers three questions: when will each piece of work happen, which pieces depend on which, and when will the project finish. Two views of the same information dominate practice:
- the Gantt chart: bars on a timeline, easy to read and to share
- the network diagram: tasks as nodes linked by dependencies, which exposes the logic and the critical path
How it works
- Start from the WBS. Its work packages become tasks (see Work Breakdown Structure).
- Estimate durations, ideally with the people who will do the work. For uncertain tasks, use three-point estimates: optimistic, most likely and pessimistic.
- Link dependencies. Finish-to-start is the most common; start-to-start and finish-to-finish handle overlap. Add lags where needed.
- Find the critical path: the longest chain of dependent tasks, which sets the finish date. Tasks off the critical path have float, so they can slip without delaying the end.
- Assign and level resources. A schedule that needs the same specialist in three places at once isn’t real.
- Set milestones: zero-duration markers at meaningful points, such as reviews, deliveries and gates.
- Baseline, then track. Save the agreed plan, record actual progress, and compare (see Earned Value Management).
In practice
The program’s lab has candidates bring a laptop with Microsoft Project or a similar tool, and first schedule something ordinary, like preparing a meal or changing a tire, to learn the mechanics before scheduling a real project. The everyday example makes the logic obvious: you can’t serve before you cook, and some things (boiling water, preheating the oven) can run in parallel. On real programs, two habits matter most:
- Watch the critical path. It moves.
- Protect the scarce resource, which is often the real constraint (see Theory of Constraints).
Questions to ask yourself
- What is my project’s critical path today, and has it moved since the plan was made?
- Which tasks have float, and is anyone using that float without realizing it?
- Are our milestones meaningful decision points, or just dates?
Connections
- Built from: Work Breakdown Structure. Tracked with: Earned Value Management. History: Origins of Modern Project Management.
- Same logic at machine scale: Throughput and Timing Analysis. Scarce resources: Theory of Constraints.
- Capabilities exercised: Realizing the Vision, Responsibility and Urgency to Deliver, Decision Making.
Sources
- Kurstedt and Kurstedt (2005) Project Management Handbook [1]
- Weaver (2007) The Origins of Modern Project Management [2]