We studied the diagnostic utility of ELISA in pulmonary tuberculosis (TBC) using serologically active glycolipid antigens. Twenty-seven patients who were smear positive, and 30 patients who were smear negative, but with evidence of active TBC (sputum culture positive in 10, response to anti-TBC chemotherapy in 20) were included in the study group. Twenty cured patients who had been free of TBC for at least 1 year, 50 TBC-free persons with PPD results of 0-10 mm and more than 10 mm, and 21 patients with active inflammatory diseases other than TBC formed the control groups. Sensitivity and specificity were 96 and 91%, respectively. We think that serologically active glycolipid antigens are as sensitive and specific as other purified antigens, and even superior to them from the point of view of their production: their extraction is quicker and easier.