OBJECTIVE: To ascertain whether case-finding through community outreach in a rural setting has an effect on case notification rate, symptom duration, and treatment outcome of smear-positive tuberculosis (TB). METHODS: We randomly allocated 32 rural communities to intervention or control groups. In intervention communities, health workers from seven health centres held monthly diagnostic outreach clinics at which they obtained sputum samples for sputum microscopy from symptomatic TB suspects. In addition, trained community promoters distributed leaflets and discussed symptoms of TB during house visits and at popular gatherings. Symptomatic individuals were encouraged to visit the outreach team or a nearby health facility. In control communities, cases were detected through passive case-finding among symptomatic suspects reporting to health facilities. Smear-positive TB patients from the intervention and control communities diagnosed during the study period were prospectively enrolled. FINDINGS: In the 1-year study period, 159 and 221 cases of smear-positive TB were detected in the intervention and control groups, respectively. Case-notification rates in all age groups were 124.6/105 and 98.1/105 person-years, respectively (P = 0.12). The corresponding rates in adults older than 14 years were 207/105 and 158/105 person-years, respectively (P = 0.09). The proportion of patients with >3 months' symptom duration was 41% in the intervention group compared with 63% in the control group (P<0.001). Pre-treatment symptom duration in the intervention group fell by 55–60% compared with 3–20% in the control group. In the intervention and control groups, 81% and 75%, respectively of patients successfully completed treatment (P = 0.12). CONCLUSION: The intervention was effective in improving the speed but not the extent of case finding for smear-positive TB in this setting. Both groups had comparable treatment outcomes.