The overall aims of the project are to compare alternative methods to ensure completion of treatment and preventive therapy for TB in inner cities, and to identify the most cost-effective methods to accomplish that. The basis for comparison includes adherence rates and cost savings as primary outcomes, and other parameters such as patient satisfaction, development of social networks, and participation in support programs as secondary outcomes. Two clinical trials are proposed to be conducted with patients from Harlem. Among those with active disease, a clinic-based surrogate family model will be compared to traditional community-based directly observed therapy (DOT). Among those eligible for preventive therapy, a community-based intervention conducted by trained graduates of a TB DOT program (peer workers) will be compared to traditional self-administered preventive treatment.