Resource smoothing is one of the project management tools used in the resource optimization techniques. It is defined as a technique that adjusts the activities of a schedule model so that all requirements for the resources do not go beyond the resource limits already pre-defined during the planning.
There are only a few reusable resources that are limitless thus the time schedules have to be imposed and adjusted to manage the limited availability of the resources in a given time. Resource smoothing is one of the tools used to reconcile the limited resources and time but a different approach than resource leveling.
It is used when the time constraint takes important priority in project planning. The objective of this project management tool is to complete the work or activity within the required date and, at the same time, avoiding peaks and troughs or the resource demand.
A smooth resource profile is usually achieved by delaying some tasks or works. This will reduce the flexibility of the schedule when it comes to dealing with delays but it is very cost effective in managing and using the resources.
This term is defined in the 5th edition of the PMBOK.