In a background of changing lung cancer rates in the past decade, mean incidence and mortality rates for persons aged 25-44 in Tasmania for the decade 1983 through 1992 were examined using Tasmanian Cancer Registry data. The smoking behavior of Tasmanian adults and schoolchildren was also investigated, using data from a social survey conducted by the Australian Bureau of Statistics and from five secondary school smoking surveys. The Tasmanian age-standardized lung cancer incidence rates in 25-44 year olds for the 10-year period were 6.2 per 100,000 females and 3.3 per 100,000 males. Mean rates of incidence were higher for females than for males (P = 0.02). The corresponding mortality rates were 4.2 in females and 2.4 in males (P = 0.08). The prevalence of smoking by adult Tasmanian women is higher than that for other Australian women (P < 0.05), and their duration of smoking is longer (P < 0.01). Tasmanian schoolgirls have a higher smoking prevalence than Australian mainland schoolgirls (P = 0.01) and higher prevalence than Tasmanian schoolboys (P = 0.01). The data suggest that smoking prevalence among teenagers passed that for males only a decade before the observed excess of female incident cases among 25-44 year olds in Tasmania.