Using data from a record-linkage between the Swedish population census of 1960 and the Swedish Cancer Registry, we performed an explorative, hypothesis-generating analysis of the incidence of thyroid cancer in 208 occupations and 231 industries. Relative risks were computed with adjustment for age, period of follow-up, and geographic region. A total of 1,230 male and 2,937 female cases of thyroid cancer were reported during 1961-1979 among individuals aged 20-69 years in 1960. As a group, male blue-collar workers had a lower reported incidence than other men. Significantly elevated risks were seen among drivers, pharmacists, workers in the canning and preserving industry, workers in the petroleum industry, and among X-ray operators and laboratory assistants. Horticulture workers, painters in the construction industry, and unskilled manual workers showed decreased risks.