Resource leveling is the adjustment of the schedule based on resource constraints. For example, if the same person is needed full-time for two different tasks, those tasks cannot be scheduled at the same time.
Contrast to resource smoothing, where activities are scheduled to conform to a specified level of resources.
See section 188.8.131.52 of the PMBOK, 5th edition.
- Wikipedia on resource leveling
- Izenbridge on Underlining the differences between Resource Leveling and Resource Smoothing? by Saket Bansal, February 12, 2014.