This timely and synoptic text contains the essentials of queueing networks, from the classical product-form theory to the more recent developments such as diffusion and fluid limits, stochastic comparisons, stability, dynamic scheduling, and optimization. Written by two leading experts in stochastic models and applied probability, the book is based on the authors' lecture notes accumulated over many years of teaching queueing networks. The selection of materials is well-balanced in breadth and depth, making the book an ideal graduate-level text for students in engineering, business, applied mathematics, and probability and statistics. As queueing networks have become widely used as a basic model of many physical systems in a diverse range of fields, from supply chains to communication networks, the book is also a useful reference for researchers and practitioners in industrial engineering, operations research and management, computer systems, telecommunications, and related fields.