Prof. Ralf S. Mueller graduated in Munich/Germany, completed his doctoral thesis in 1987, and worked in several large and small animal practices before completing a residency in veterinary dermatology at the University of California/Davis in 1992. In 1992 he moved to Melbourne/Australia to work with his partner and wife Dr. Sonya Bettenay. Together, they created the first, purpose-built specialist practice in Australia. During that time, Dr. Mueller was concurrently consulting and teaching at the Veterinary Teaching Hospital/University of Sydney. Ralf and Sonya established (and continue to conduct) the Distance Education Program in Veterinary Dermatology of the Centre for Veterinary Education of the University of Sydney. In 1999, Ralf became Assistant Professor in Veterinary Dermatology at the College of Veterinary Medicine and Biomedical Sciences/Colorado State University. In 2004, he accepted a position as chief of the veterinary dermatology service at the University of Munich/Germany that he held until 2026. His main research interests were allergies and ectoparasites. Since 2026 he works as an independent consultant. He has published over 300 studies, articles, book chapters and books and given more than fifteen hundred seminars, lectures and talks all over the world.