Reserving Slots on Teamspeak

Teamspeak 3 offers the option to reserve slots. By default, the ServerAdmin group has access to these reserved slots.
The reserved slots are held open. Unfortunately, this function is still somewhat flawed in the current TS3 server.
If you have a server with 25 slots, specify 15 slots as reserved, and then have 10 ServerAdmins on the server,
no one who is not in the ServerAdmin group can access the server.

How do I set up reserved slots?

Simply select Extras and then Edit Virtual Server when connected to the server.
In the window that pops up, you will see the Reserved Slots next to the Maximum Number of Clients for the server.