A medico-social study was conducted at the New Delhi TB Center to determine the factors involved in late diagnosis. A total of 400 new patients attending the Center from three different territories, were interviewed for information on the duration of symptoms and remedial action taken by them before reporting at the Center. The resulting data were then correlated with the clinical and bacteriological status of each patient to ascertain the consequences of late diagnosis for the patient. The results, based entirely on patients' narrations, indicated that patients' late visit to the Center was because of late diagnosis or referral. A concerted effort is necessary to promote awareness of TB among the general public and to ensure that GPs and General Health Institutions suspect TB early and diagnose or make referrals early.