Book excerpt: This respected graduate-level textbook provides comprehensive and accessible coverage of the basic and clinical aspects of the mucosal immune system, addressing the major components of the mucosal barrier ̶ gastrointestinal, upper and lower respiratory, ocular, and genitourinary mucosal immune systems ̶ in a highly user-friendly style. The editors of and contributors to the book, all internationally-recognized leaders, present the current principles, concepts, and basic processes involved in mucosal immunology, mucosal diseases, and host defense at mucosal surfaces. Topics discussed include the development and structure of the mucosal immune system and its cellular constituents, host-microbe relationships, infection, mucosal diseases, and vaccines. The second edition has been carefully updated throughout to reflect the latest developments from clinical research and key literature has been fully updated.