Following several senior positions and 13 years in health service laboratories, G. O. Evans left the post of principal clinical chemist at Birmingham Children’s Hospital, England, to enter the field of laboratory animal toxicology and clinical pathology. He was head of clinical pathology at Wellcome Research Laboratories, Beckenham, England, moving to join Astra Charnwood, and later the two AstraZeneca sites in the United Kingdom as director of clinical pathology. Evans is now a director of A. George Owen and Company. He was the editor of and a contributor to a number of chapters of the book Animal Clinical Chemistry: A Primer for Toxicologists. In addition to lecturing at various universities in the UK, he has published over 40 papers on animal clinical pathology and toxicology. Other activities have included membership on the editorial board of the journal Laboratory Animals for over 15 years, and he has served as scientific secretary, chairman, and now is a lifetime honorary member of the Association of Comparative Clinical Pathology, UK.