All 515 patients notified for tuberculosis for the first time in 1972, 1977 and 1982 in Copenhagen have been studied. Changes during the period and differences between Danes and immigrants were looked for. The percentage of immigrants increased during the period. The immigrants had a different age distribution, higher frequency of extrapulmonary tuberculosis with a distribution different from that of Danes, fewer complicating diseases and they drank less alcohol. No significant changes in the patient population took place in the decade studied, except for a decreasing number of Danes with tuberculosis, a decreasing number of abacillary patients and an increase in the percentage of extrapulmonary tuberculosis. At follow-up in 1983, none of the immigrants, but 147 of 407 Danes had died, mainly from complicating diseases. Life expectancy for the Danes, who survived the initial phase, was not significantly different from that for the population at large. None of the patients were bacillary at the time of the follow-up.