Attitudes towards mental disorders have been studied in rural areas of Sudan and Northern India and an urban area of the Philippines using standardized interviews with key informants. On average each informant knew by name 3.6 individuals who corresponded to descriptions provided of common mental disorders. The conditions most frequently identified were mental retardation (in all three areas), alcohol and drug related problems (in the Sudanese and Philippines areas) and acute psychosis (in the Indian area). In the Philippines area, the majority of informants indicated traditional healers as the primary source of help for psychological symptoms; in all areas people were judged to be more likely to seek help for psychological than for physical symptoms from traditional healers. Perceptions of mental illness and their consequences have been presented in graphic form through “attitude profiles”. These reveal differences in responses to the seven mental disorders presented to the key informants through vignettes. More negative and pessimistic attitudes were found in the Indian area than in the other two areas. The study has been carried out within a programme to introduce community based mental health care as part of primary health care in developing countries. The results have already been used in selecting priorities and designing interventions to promote community involvement. Their eventual use in evaluating the effectiveness of new forms of mental health care is also described.