The Task Effort is the sum of the Work (hours) of all Work Type resources assigned to a task.
The Effort driven option determines how the effort is calculated as resources are added or removed from a Fixed Units or Fixed Duration task.
There are two options in MS Project:
|Effort driven||When a resource is added or removed from a task, the Task Effort assigned to a task remains constant. Therefore the Work of existing Resources is reduced when a new resource is assigned. Adding or removing resources from a task will leave the total effort assigned to a task constant, unless all resources are removed or a change is made to the work of existing resource assignments.|
|Non Effort driven||When a resource is added to or removed from a task, the Resource Effort or Work of other resources remains constant. Adding or deleting resources increases or decreases the total task effort and will not change the effort of assigned recourses.|
In summary, as you assign resources:
– If you want the total number of hours assigned to stay constant then make the Task Effort driven.
– If you wish to assign each resource with its own hours or units per time period then make the task Non Effort driven.
Note: A Fixed Work task is automatically Effort driven.