Dr John Walker is a University of Sydney alumni who worked at the Sydney School of Public Health and Westmead Hospital as a Senior Lecturer in Parasitology for 38 years. His work focused on diagnostic parasitology and epidemiological surveys of gastrointestinal parasites, malaria and filariasis. A major emphasis of his latter work was providing malaria reference laboratory services and maintenance of a register of malaria cases imported into NSW. Dr Walker retired in 2005 but has retained his interest in parasitology.