A study was made of the incidence of basal cell cancer among a population of residents within a limited catchment area in Stockholm during the period 1971-1980. The age-standardized incidence of basal cell cancer increased by an average of 11.9% per year (p less than 0.005) and the incidence rate more than doubled during the ten-year period. There was no statistically significant difference in the rate of increase for men and women. Nor was any such difference noted between face, head and neck and other skin areas.