Control Resources is the last of the lot when it comes to the processes in the Resource Management knowledge area. Below is the PG-KA mapping,

The process of Control Resources majorly ensures three things,
- Assigned physical resources are available and released as planned
- Monitor planned vs actual resource utilization or, in other words, monitor resource expenditures
- Take corrective action as required i.e. address resource shortage or surplus in a timely manner
Obviously, there are other items to take care of, for instance, keeping stakeholders informed in case there are issues with the relevant resources or managing changes as they occur. Note that any change required in the schedule or cost baseline will go through the Integrated Change Control process.
It should be obvious that this process is performed throughout the project lifecycle because you won’t need all the resources all the time!
Also, if you didn’t notice, control resources process deals only with physical resources like equipment, materials, facilities, infrastructure etc. Manage Team process addresses the team resources.
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