Project Planning and Scheduling Using Primavera Version 4.1: For Engineering & Construction and Maintenance & Turnaround

Preferences that affect how all resources in a project calculateare set in the Project Workspace and pertain to all activities andresources.
Preferences set in the Activity Workspace decide how eachindividual activity and resource calculate and are covered in the next section.
The Resources tab in the Projects Workspace:

Resource Assignments. Checking the Resources can be assigned to the same activity more than once box allows aresource to be assigned to an activity more than once. This is useful if it is required to assign aresource at the beginning of an activity and later at the end of an activity with a lag.
Drive activity dates by default. A resource has thefollowing fields that are linked and a change to one will make a change to another:
Original Lag. The duration from the Activity Start Date tothe Resource Start Date, which is the date the resource commences work.
Original Duration. The duration that a resource isworking.
Start. The Resource Start Date =Activity Start Date + theResource Original Lag.
Finish. This date is calculated by the addition of theActivity Start Date + Original Lag + the Original Duration.
With this option checked, a resource will be assigned to an activity with the Drive Activity Dates field checked and then Activity Finish dateis calculated from the latest Resource Finish date that has the Driving Activity dates optionchecked.

With this option unchecked, a resource will be assigned to an activity with the Drive...