This study describes the smoking patterns of 3528 construction workers as reported at occupational health examinations, in four occupational health centres located in the South of Germany, conducted between August 1986 and December 1988. Subjects were aged 20 to 59 years and were working as plumbers, carpenters, painters or varnishers, plasterers, bricklayers, unskilled workers or white collar employees. Overall smoking prevalence was 53.5%. It was considerably higher than in a representative population sample of the same age groups. Active follow up was carried out to ascertain vital status between October 1992 and July 1994. The effect of smoking on all cause mortality was assessed using the cox proportional hazard model. The relative risk of current smoking was 2.5 (95% CI 1.4-4.4) after adjustment for age, profession, self reported alcohol consumption, body mass index, nationality, and company size. 60% of the deaths among smokers and 34% of deaths in the whole cohort were attributable to smoking. These findings underline the need for comprehensive efforts to reduce smoking and its negative consequences in the occupational group.