This volume presents a timely and comprehensive overview of biological networks at all organization levels in the spirit of the complex systems approach. It discusses the transversal issues and fundamental principles as well as the overall structure, dynamics, and modeling of a wide array of biological networks at the molecular, cellular, and population levels. Anchored in both empirical data and a strong theoretical background, the book therefore lends valuable credence to the complex systems approach. Contents: Scale-Free Networks in Biology (E Almaas et al.); Modularity in Biological Networks (R V Solé et al.); Inference of Biological Regulatory Networks: Machine Learning Approaches (F d Alché-Buc); Transcriptional Networks (F Képès); Protein Interaction Networks (K Tan & T Ideker); Metabolic Networks (D A Fell); Heterogeneous Molecular Networks (V Schächter); Evolution of Regulatory Networks (A Veron et al.); Complexity in Neuronal Networks (Y Frégnac et al.); Networks of the Immune System (R E Callard & J Stark); A History of the Study of Ecological Networks (L-F Bersier); Dynamic Network Models of Ecological Diversity, Complexity, and Nonlinear Persistence (R J Williams & N D Martinez); Infection Transmission through Networks (J S Koopman).