There are various Administrator Roles available which you can assign to users of your facility. These roles allow others to make changes to your account, within their specific role. Further details on the roles are available here: Administrator Roles
For example, if you decide to assign full 'Administrator' rights to a user, they will be able to make changes to all areas of your account.
A 'Court Reservation Administrator' can only make changes to the Court Reservation module, a 'Contacts Administrator' can only make changes to the Contacts area, and so on.
In the Admin Area of your account, click on "Administrators" on the left-hand side.
Select 'Add Administrator' in the top right:
Then choose one of the following:
a) Fill in the details as required (this option is for a new contact, not already registered), or;
b) Select 'Existing Contact' and type in a name to lookup from your Contact list.
Tick the box corresponding to the Administrator role you wish to assign to the contact. You can remove a role by unticking the box and pressing save.
Remembering that the 'Administrator' role will give a user full admin rights. The 'Super Administrator' role has the same rights as the Administrator role but can also revoke Administrator rights. All the other administrator roles will give a user admin rights to the corresponding module.
To remove an administrators access - Note: only Super Administrators on Serve Tennis have this right.
If there is no super administrator on your Serve Tennis account then please contact Customer Care.
Step 1: Click on the administrator you wish to remove from the the administrator tab.
Step 2: This opens up the administrators contact - click on Profile Options and Edit Contact
Step 3: Scroll to the bottom of the page to Administrators Roles
Untick the administrator role, so the box is empty. 
Step 4: Save Contact
Step 5: If you want to delete them entirely. After you have removed their admin rights and saved you will then be able to delete the contact by clicking on profile options again and delete contact.