Your best developer is booked at 150% next week and the launch date can't move. What do you do? The PMP exam answers this with two techniques that sound similar but behave very differently: resource leveling and resource smoothing.
First, spot the problem: the resource histogram
A resource histogram shows how much of one person's time is booked, week by week. Any bar above the capacity line (100%) is an over-allocation, usually caused by two activities overlapping.
The two fixes
| Resource leveling | Resource smoothing | |
|---|---|---|
| What it does | Moves activities until nobody is over-allocated | Moves activities only within their float |
| End date | Can move later (can extend the critical path) | Never moves |
| Fixes every conflict? | Yes | Not always |
| Use when | The conflict must be fully resolved, and the date can move | The deadline cannot move |
The rule for the exam
- "The deadline cannot move" → smoothing.
- "The over-allocation must be fully resolved, a later finish is acceptable" → leveling.
- Crashing and fast tracking don't fix an over-allocated person. They're schedule compression techniques, not resource techniques.
Example: one specialist, two projects
Two projects need the same database specialist in the same month, and both project managers want her full time. Instead of fighting over her, they go to her functional manager together, with each project's priority and the impact of waiting. The result: project A gets her mornings for two weeks, project B gets her afternoons, and a contractor covers the overflow. Resource conflicts are solved with priorities and data, not by pulling harder.
Plan resources before they conflict
- Estimate team and physical resources bottom-up, per activity.
- Check resource calendars: an estimate without availability is just a wish.
- Assign ownership with a RACI chart, with exactly one "Accountable" per row.
- Track planned vs actual use, and raise gaps early.
Learn it with animations
The free chapter Plan and Manage Resources shows leveling and smoothing on an animated Gantt chart with the resource histogram underneath, plus practice questions. Then check yourself on the free full PMP mock exam.