Hand eczema is the most frequent occupational skin disease. Our aim was to study changes in its prevalence in Swedish adults. Cross-sectional studies were performed in 1983 and 1996. Random samples from the population of Gothenburg, Sweden, aged 20-65 y, were drawn from the population register. Data were collected with a postal questionnaire, which was identical in the two studies. The response rate was 83.5% (16,708 out of 20,000) in 1983 and 73.9% (2218 out of 3000) in 1996. The reported 1 y prevalence of hand eczema decreased from 11.8% in 1983 to 9.7% in 1996 (p < 0.01), a large difference being found in the youngest age group. Reported childhood eczema increased from 10.4% to 12.4%, however (p < 0.01). Of those with childhood eczema 27.9% and 25.2% reported hand eczema, compared to 10.0% and 7.5% among those without childhood eczema. In total 76.8% were gainfully employed in 1983 and 68.3% in 1996 (p < 0.001). In 1983 23.0% were employed in "high-risk" occupations for hand eczema compared to 19.4% in 1996 (p < 0.001). Even though the increase in childhood eczema was largest in the youngest group, there was a large decrease in the prevalence of hand eczema in that age group among both sexes. The study indicates that the prevalence of hand eczema in Swedish adults had decreased between 1983 and 1996 despite an increasing prevalence of childhood eczema. Secular changes in reporting hand eczema and childhood eczema may explain some of the changes, but a decreased occupational exposure to skin irritants is a probable cause, implying that occupational factors may be important predictors of hand eczema.