This study was done to investigate malaria case management at the community level in Gezira, Sudan, which is an area of unstable malaria predominantly due to Plasmodium falciparum. Questionnaire surveys were conducted at four consecutive weekly intervals in October 1995. A sample of 400 households (3062 persons) including 200 rural and 200 urban households was studied. Use of antimalarials was assessed in terms of diagnosis, types of antimalarial used, self-medication and compliance. During the four weeks of observation, 25.1% of the rural population and 35.6% of the urban population received at least one course of antimalarial drugs. Diagnosis was confirmed microscopically in 81.7% of treated persons in the urban community and in only 34.3% those treated in the rural community. Chloroquine is the most frequently used antimalarial in both communities with notable overuse of injections in rural patients and in patients treated by paramedical health workers. Self-medication was commoner in rural than in the urban population (41.2% versus 23.9%). Compliance with the standard therapeutic doses was poorest with quinine and best with sulfadoxine/pyrimethamine. It is suggested that interventions to improve the use of antimalarials should include health education, training of health workers and dissemination of national treatment policies.