Resource leveling is a way to resolve having too much work assigned to resources, known as resource over-allocation. One way to level is to delay a task until the assigned resource has time to work on it. Another method is to split a task, so that part of a task is done when planned, and the rest of it is done later when the assigned resource has time.

Resources can be leveled by the user or Microsoft Project can level resources. The Microsoft Project leveling feature examines the following factors to determine which tasks should be delayed or split:

When Microsoft Project levels resources, it does not change resource assignments, and it does not change task information. It only delays or splits tasks. When the user levels resources, the same factors should be taken into consideration, and the task or resource adjusted to resolve over-allocations. For example, the task can be delayed, or additional resources assigned. The methods chosen to reduce over-allocations depend on the limitations of the project, including budget, resource availability, finish date, and the amount of flexibility available for scheduling tasks.