ZigBee, 802.15.4 and other wireless technologies are changing the way engineers address problems, especially when it comes to sensors and controls. Krishnamachari’s book explores the how and why of wireless networking. This type of overview is invaluable to anyone working in this area, especially those new to this type of distributed wireless system. As with most tech books, this starts with an overview and delves into specifics. It starts at a level that even the greenest designer can appreciate. Though there are a host of equations and technical details that explain various approaches, the average developer will not drown in the details. This makes the book an excellent tool for novice and expert alike. The book covers a wide range of issues that challenge designers of wireless sensor and control systems. It starts with locality and time synchronization and moves onto sleep scheduling and robust routing. It even addresses design approaches such as data-centric networking. I especially like the breadth of the book; it doesn’t focus on a particular aspect in detail. That’s consistent, however, with the field, which is so wide that a broad approach is needed to understand the issues and interactions of designing a system. Even if you plan on doing some cookbook ZigBee designs, get this book. I cover this area and there were a host of issues, details and approaches that I was unaware of until I had a chance to read it.