This third edition volume expands on the previous editions with more detailed research on the characterization of antibody antigen interactions between different users with different requirements. The chapters in this book are divided into four parts: Part One looks at the entire native antigen and covers traditional structural biology techniques such as nuclear magnetic resonance and x-ray crystallography. Part Two talks about protein fragments derived from antigens, and discusses binding regions within antigen sequence using bacterial surface display and ELISA, for example. Part Three describes the use of surface plasmon resonance spectroscopy and biolayer interferometry, and Part Four highlights methods used to identify new antigens and assess antibody cross-reactivity. Written in the highly successful series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readilyreproducible laboratory prools, and tips on troubleshooting and avoiding known pitfalls. Thorough and cutting-edge, is a valuable resource for anyone interested in furthering their research in this expanding field.