For those not familiar with the Hacking Exposed series of books, they are not for the networking/security newcomer and delve into the depths of reality hacking, tools and techniques that are actually used in the field. They show what is used, how to use it and how to effectively protect against it. These books are a must for any penetration tester, security admin or general network/system admin that has to deal with security. Until you really know what is out there and understand it, you can't hope to defend against it. The guts of the books stay the same, operating systems, networking, switches/routers etc with the addition of a Wireless section and and expansion of other sections that have become more relevant.