This handbook is the first to present a unified, comprehensive treatment of graph theory, combinatorial optimization, and related algorithmic issues. It covers numerous topics of interest in applications in electrical, communication, computer, social, transportation, biological, and other networks. The book provides readers with the algorithmic and theoretical foundations to understand phenomena as shaped by their graph structures, develop needed algorithmic and optimization tools for the study of graph structures, and design and plan graph structures that lead to certain desirable behavior.