Although this book's full value will be realized if you understand the C programming language (he uses source code it illustrate points throughout the book and provides a C library for performance analysis on the accompanying disk), anyone with good math skills will gain much from this outstanding book. The core approach is Performance By Design, which is aligned to product development. His approach, if used properly, will ensure that performance goals are established in the design phase, and are met as a system or software evolves through the development life cycle. Highlights of the book are: (1) Through introduction to the foundation of performance: queuing, parallelism and multiprocessor systems. (2) Coverage of contemporary issues, such as client/server and web system performance, (3) Unexpected forays into performance characteristics and considerations that I've encountered in no other book. For example, Part 3 of this book addresses subtle issues such as transient analysis, scaling behavior and similar topics. Here the author integrates theoretical physics into performance analysis - while this may seem odd, it only reinforces that much can be added to the performance analysis body of knowledge by drawing from sources outside of computer science. His qualifications for this material includes a Ph.D in theoretical physics, and his ability to clearly explain concepts that are foreign to the average computer scientist or performance practitioner is excellent. I like the conversation style that the author employs, the way he starts with the basics and builds upon them and the thoroughness in which all aspects of performance are discussed. More importantly, although advanced math concepts are introduced the way they are presented can be understood by anyone with high school or college freshman knowledge of probability and calculus.