Our team has made significant progress in the development of new TB diagnostic tools in Per that demonstrate significant advantages over the gold standard diagnostics in adults. We propose to evaluate the potential of these new tools as well as others for the detection and direct susceptibility testing of Mycobacterium tuberculosis (Mtb) in children from 0-5 years of age. This project will be set in Uganda , where pediatric TB and HIV co-infection are major problems. We hypothesize that the diagnosis of active TB in children and the recovery of Mtb isolates can be done more quickly, efficiently, and cost-effectively using alternative clinical specimens in combination with more rapid diagnostic methods for both confirmation of TB and detection of drug resistance. If our hypothesis is correct, use of these methods will allow clinicians to institute rapid treatment directed specifically against the bacterial isolate from the infected child, improving the speed and outcome of anti-tuberculous therapy.