This second edition volume expands on the previous edition with discussions of the latest advancements and methods used by scientists to study systems biology. The chapters in this book are organized into four parts. Part One looks at models in systems biology and parameters identification such as short peptide analysis, metastasis models, and metabolomics. Part Two covers computational methods in the study of organisms, and cancer non-linear dynamics. Part Three discusses critical transition states across Waddington’s like landscapes such as understanding cell differentiation through single-cell approaches and modeling mammary organogenesis from biological first principles. Part Four talks about specific fields of investigation including inborn errors of metabolism, system biology approach in epithelial-mesenchymal transition, and an approach to understanding how COVID-19 spreads in the population. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Cutting-edge and comprehensive, Systems Biology, Second Edition is a valuable tool for any researcher looking to learn more about this important and developing field.