The Division of Parasitology is intertwined with the history of the Indian Veterinary Research Institute when one realizes that one of the first problems handled by the Institute was determining the etiology of 'surra', a haemoprotozoan disease of horses caused by Trypanosoma evansi. During the early part of the century, the equine-stud problems on surra, filariasis and the once-mistaken role of insects in the transmission of rinderpest attracted the attention of researchers. In order to address the above issues, a Section of Protozoology comprising of Protozoology and Entomology units was created in 1931 with the Director as In-charge, and by 1939, this Section was renamed as Veterinary Zoology with a Parasitologist as In-charge. Subsequently, by the year 1954, the Section of Parasitology was elevated to the status of a full-fledged research Division. Since inception, the Division of Parasitology has been actively involved in basic and applied research on parasitological problems of national importance. The emerging priority areas of parasitic infections in sixties and seventies established linkages with international agencies like UNDP/ IAEA for Dictyocaulus vaccine production which received a further fillip for development of diagnostic and prophylactic measures against Anaplasma and Theileria infections. Based on these pioneering contributions, an Indo - US project (1987 - 1992 ) and an All India Coordinated Research Project (1992 -2002) on haemoprotista were sanctioned which greatly facilitated strengthening the infrastructural facilities and the expertise at the division. Prestigious research projects like National Agricultural Technology Project on "Diagnosis of Parasitic Diseases of Domestic Animals" and All India Network Programme on Gastrointestinal Parasitism were completed in the years 2004 and 2021, respectively. In continuation, another prestigious programme entitled, “Study of herbal acaricides as means to overcome the development of resistance in ticks to conventional acaricides” started under National Agricultural Innovation Project. During 2007-15, a project on Niche area of Excellence entitled “Production and quality control of veterinary immunodiagnostics and immunoprophylactics” and an international project entitled “Integrated Consortium on Tick and Tick-borne Diseases” funded by European Commission were completed. In the last decade four patents were received and a technology was transferred to commercial house. Five reference tick lines (both acaricide resistant and susceptible) were established in the Division. Four more patents have been submitted for approval. Currently the division has full-fledged laboratories for helminths, arthropods, and protozoal infections of domestic and wild animals. Besides research, the divisional scientists are regularly providing subject matter specialist services to the stake holders and imparting undergraduate and postgraduate education as well as imparting training on diagnosis, control and management of parasitic infections in animals to various stakeholders like livestock owners, para-veterinary staff, veterinary doctors of state departments and para-military forces and teachers of various veterinary colleges/ universities.