Rapid advances continue to be made in all areas of immunology, not least the biology of the immunoglobulins. This knowledge has resulted in a better understanding of antibody responses and helped to clarify pathogenic mechanisms in many diseases, particularly autoimmune and allergic diseases, as well as expand our comprehension of antibody deficiency diseases and mechanisms in therapeutic immunization. In addition, the recognition that diverse disease states may result in abnormalities of the amount of immunoglobulins in body fluids has resulted in the use of immunoglobulin assays for disease diagnosis and management. The aim of this book has been to condense both the established and recent aspects of this knowledge, particularly that pertaining to clinical immunology. The contributions of different authors hopefully provide a comprehensive review of their particular field of interest as well as a discussion of how this information can be applied to clinical medicine. Immunological terms and concepts have been explained where appropriate so that the book can be read by those with only a basic knowledge of immunology. In producing a book on this one area of immunology some duplication of information has been accepted so that topics can be considered in different contexts. I hope the book will be of value to those in training or already pursuing a career in clinical or laboratory medicine by providing a basic and short text on immunoglobulins. M.A.H.F.