Tuberculosis Research Centre, Chennai has been conducting randomized controlled clinical trials in both adults and children (n = 1015) in various non-pulmonary forms of tuberculosis, for the last two decades. This communication discusses the salient findings of these studies. The important finding is that short course chemotherapeutic regimens have been proven to be highly effective in tuberculosis of spine, superficial tuberculous lymphadenitis, abdominal tuberculosis, brain tuberculoma and Pott's paraplegia. However, in tuberculous meningitis, the outcome appears to be directly related to the stage of the disease on admission. The intermittent regimens have been found to be as effective as daily regimens. The other important aspects highlighted are the need to obtain bacteriological/histo-pathological confirmation by resorting to relevant diagnostic procedures, value of Mantoux as a diagnostic tool and role of surgery.