This issue of Veterinary Clinics of North America: Small Animal Practice, edited by Bruce W. Christensen, focuses on Small Animal Theriogenology, with topics including: Assisted Reproduction in Male and Female Cats, Population Control in Small Animals, Practitioners considering SA Therio, Evaluation of Canine Sperm and Diagnosis of Semen Disorders, BSE in the Canine Female, Artificial Insemination in Dogs, Estrus Manipulation in Dogs, Endocrine testing in Small Animals, Endocrine Disruptors, Mismating Diagnosis and Protocols, Gestational Aging and Assistant Parturition Date Determination, Small Animal Pyometra, Periparturient Diseases in the Dam, Small Animal Neonatal Health, Herpesvirus, Prostate Disease, and the Future of Biotechnology.