In the District Tuberculosis Programme in India, which is part of a national programme, case-finding and treatment of pulmonary tuberculosis are integrated into the general health services. With such an integration, it is desirable, in order to forecast possible achievements, to understand the additional work-load that the programme will impose upon the existing health institutions and to assess the potential of these institutions for case-finding and treatment.The operational study described in this paper was made under programme conditions in a district in South India and is an examination of the case-finding potential of rural health institutions, using direct microscopy of sputum for diagnosis, and of the additional work-load involved by such case-finding. Under the conditions found in the course of the study, it is clear that a substantial proportion (at least 65%) of pulmonary tuberculosis cases prevalent in the district can be detected by the existing staffs with an easily manageable work-load.