I am the network administrator of a pretty big company. We put in ISA Server last year. I wish I had this book then. I can't tell you how many times I could have used this. It explains how to do basic stuff like block certain sites or make our Outlook server available using OWA, how to publish a web server, and how to lock down the environment to keep the bad guys out.

The book is sometimes short on theory and the reasons why stuff workes the way it does, but if you want something that is just down to the basics, though, this is a killer book that can help you use ISA easily.