located on the Camperdown campus of the University of Sydney. His earliest research was incorporated in the groundbreaking publication (Clunies-Ross and Gordon) "The Internal Parasites and Parasitic Diseases of Sheep". This research came at a time when Australian woolgrowers were suffering enormous losses due to failure to identify parasites causing losses, lack of treatment, and limited knowledge of the factors leading to pasture infection. University of Sydney Gordon was a part-time lecturer in Veterinary Parasitology at the University of Sydney from 1937 until 1970. During this time he was responsible for teaching more than 1000 future veterinarians. Following his retirement from the CSIRO in 1974, he resumed teaching at the University of Sydney as a part-time demonstrator in Veterinary Parasitology. He continued in this role until 1996. In 1968 he was awarded the Degree of Doctor of Veterinary Science from the University of Sydney for his thesis "Studies on Helminthosis in Sheep". McMaster Laboratory, CSIRO Gordon was appointed to the staff of the McMaster Laboratory in 1934, and remained there until his retirement in 1974. Gordon's time at the McMaster laboratory was marked by a prolific output of substantial papers, encompassing laboratory research and results from numerous field studies. Gordon's major contribution was in laying the foundations of modern epidemiological thinking in the control of internal parasites of grazing ruminants, and sheep in particular. His understanding of the epidemiology of internal parasitism and parasitic diseases of sheep allowed him to develop control strategies that minimised reliance on drenching. Dr Gordon's ideas were quickly recognised internationally, and in the 1960s and 70's he was frequently invited to make major contributions to International Veterinary Conferences and present invited specialist lectures in Europe, North and South America and South Africa. The internationally recognised Wormkill program, which was most effective at controlling worms in the New England region of New South Wales in the 1980s, was based on principles developed by Gordon in the 1940s. In addition to his epidemiological research, Gordon also researched and published extensively on the use of various anthelmintics in sheep. He was responsible for the discovery in the late 1930s of phenothiazine, a safe and effective anthelmintic. His research showed that this compound could effectively control intestinal parasites in sheep and cattle. This discovery, and local production of the required chemicals, resulted in a massive cut in the economic losses suffered by farmers due to intestinal parasitism. Phenothiazine was