4. Study Procedures: This study will involve 3 years of follow-up of patients who had been initiated on a course of TB therapy as part of the SAPIT and START trials. Upon exit from the SAPIT trial (i.e. 18 months post-TB diagnosis), study patients will be consented and enrolled in this cohort study. Study participants will be seen monthly for the first 3 months and thereafter 3 monthly, for routine clinic visits and ART services. At every visit patients will be screened for TB recurrence clinically, with chest radiograph and, whenever possible, with available TB diagnostics or new diagnostics that are being developed and/or tested.