I really liked the Core book, so I bought this one. I use these books to get an overview of the application. Then I go to class or read a more detailed self-study book. Before taking the test, I read through the Nutshell book 1 more time. The information is VERY condensed, so you have to read every word. I think that it does a good job of making sure that you didn't miss any important subjects. I have used it for the TCP/IP and Exchange 5.5 tests. I will continue to buy these nutshell books in the future.