Bovine cerebral theileriosis (BCT) has been ranked as the highest disease priority by pastoralist communities in Northern Tanzania and is considered a severe constraint to increased livestock production. The study incorporated a participatory rural appraisal survey carried out from September – November 2001, followed by longitudinal studies in selected study sites, field monitoring and treatment of affected cases and collection of post-mortem samples at slaughter slabs in pastoral areas. Gross pathology and histo-pathology work was carried out in collaboration with Turin University. The planned outputs of this research programme were to confirm the incidence of the disease; to assess its true social and economic impact; and to record the presence of haemoparasites and other possible disease agents and risk factors. Appropriate control methods were to be developed based on a thorough understanding of the epidemiology of BCT.