This book is written for computer engineers and scientists active in the development of software and hardware systems. It supplies the understanding and tools needed to effectively evaluate the performance of individual computer and communication systems. It covers the theoretical foundations of the field as well as specific software packages being employed by leaders in the field. ? written by a scientist successful in performance evaluation, it is based on his experience and provides many ideas not only to laymen entering the field, but also to practitioners looking for inspiration. The work can be read systematically as a textbook on how to model and test the derived hypotheses on the basis of simulations. Also, separate parts can be studied, as the chapters are self-contained. ? the book can be successfully used either for self-study or as a supplementary book for a lecture. I believe that different types of readers will like it: practicing engineers and researchers dealing with new solutions, as well as graduate students starting their adventures in the jungle of performance evaluation. -Piotr Cholda, in IEEE Communications Magazine, October 2011