Data from the US population-based Third National Health and Nutrition Examination Survey, conducted from 1988 to 1994, were used to estimate the population prevalence, prevalence odds ratios, and attributable fractions for the association of chronic obstructive pulmonary disease (COPD) with employment by industry and occupation. The aim was to identify industries and occupations at increased risk of COPD. COPD was defined as forced expiratory volume in 1 second (FEV(1))/forced vital capacity <70% and FEV(1 )<80% predicted. The authors used SUDAAN software (Research Triangle Institute, Research Triangle Park, North Carolina) to estimate the weighted population prevalence and odds ratios using 9,823 subjects aged 30-75 years who underwent lung function tests. Odds ratios for COPD, adjusted for age, smoking status, pack-years of smoking, body mass index, education, and socioeconomic status, were increased for the following industries: rubber, plastics, and leather manufacturing; utilities; office building services; textile mill products manufacturing; the armed forces; food products manufacturing; repair services and gas stations; agriculture; sales; construction; transportation and trucking; personal services; and health care. Occupations associated with increased odds ratios for COPD were freight, stock, and material handlers; records processing and distribution clerks; sales; transportation-related occupations; machine operators; construction trades; and waitresses. The fraction of COPD attributable to work was estimated as 19.2% overall and 31.1% among never smokers.