Universal Resource Scheduler Licence

Hi All,

I have a customer using Dynamics 365 Sales. They have a requirement to schedule a custom entity.
We were looking at using the Universal Resource scheduler.
I can see that a Customer Service or Field Service licence is a pre-requisite.
Can anyone tell me, do I need a licence for each user in the system, or just the user doing the scheduling?

Any advice appreciated,
Thanks,
Gerry.