The options discussed on this page are found by selecting Menu --> Setup --> Appointments 

The ‘Staff Restrictions’ function allows rules to be put in place about which appointment types can be performed by each staff member. Two levels can be set, ‘Warned’ or ‘Not Allowed’. This is shown and explained below:

The Appointment Reasons are shown in the left hand table. In the right hand table, for each appointment reason you can select a Staff Member and choose whether or not the staff member is allowed to conduct this appointment, by ticking Warned or Not Allowed.