Book excerpt: Immunological Aspects of Reproduction in Mammals contains papers presented during a symposium at the University of Nottingham Easter School. The scholarly presentations provide a wealth of information on the field of reproductive immunology and indicate just how complex this field is and how many questions still remain to be answered. The book begins with reviews of the current status of the complexities and uncertainties of the cellular basis of the immune response and the structure and function of antibodies. This is followed by separate chapters on the assessment and interpretation of the phenomena surrounding autoimmune and isoimmune reactions to spermatozoa; advances in defining the distribution and degree of exposure of major histocompatibility antigens; the reproductive immunology of the mouse, horse, and sheep; and fetal and neonatal immunity. Subsequent chapters present studies of immunization of several species with either the hypothalamic hormone LH-RH, pituitary gonadotrophins, or ovarian steroids; and studies directed towards efforts to enhance animal production by either active or passive immunization of female farm animals against steroid hormones. This book will be a valuable reference text for those already involved in the field and a stimulus for others to enter this complex and fascinating area of research.