We analyzed mortality trends among people who died with a diagnosis of obstructive lung disease from 1979 through 1993, using death certificate reports of 31,314,160 decedents in the Multiple-Cause Mortality Files compiled by the National Center for Health Statistics. Of all the decedents, 2,554,959 (8.2%) had a diagnosis of obstructive lung disease (ICD-9 490 to 493.9, 496) listed on their death certificates; of these 2,554,959 decedents, only 1,106,614 (43.3%) had obstructive lung disease listed as the underlying cause of death. The age-adjusted mortality rate increased 47.3%, from 52.6 per 100,000 in 1979 to 77.5 per 100,000 in 1993. The age-adjusted mortality rate increased 17.1% among men, from 96.3% per 100,000 in 1979 to 112.8 per 100,000 in 1993, whereas this rate increased 126.1% among women, from 24.5 per 100,000 in 1979 to 55.4 per 100,000 in 1993. Over the study period, white males had the highest mortality rates (98.8 to 115.5 per 100,000), followed by black males (77.5 to 100.2 per 100,000), males of other races (38.1 to 58.6 per 100,000), white females (25.5 to 57.7 per 100,000), black females (14.9 to 38.5 per 100,000), and females of other races (10.9 to 20.9 per 100,000). We conclude that mortality related to obstructive lung disease is under-estimated in studies that look at only the underlying cause of death. Mortality rates of obstructive lung disease are starting to stabilize among men, but continue to increase among women, reflecting historical smoking trends in these populations.