OBJECTIVE: To estimate the national prevalence of smoking. DESIGN: A total of 4820 adults aged 16 years and over (2364 men, 2456 women) were surveyed throughout Australia in 1989 by a large market research company. SETTING: Interviews were conducted in the participants' homes. RESULTS: Overall, 30.2% of men and 27.0% of women were current smokers; 29.8% of men and 19.3% of women were past smokers. The mean daily consumption of factory-made cigarettes among male smokers was 22 and among female smokers 18.9. Taking into account the published tar content of the brand smoked, it was estimated that the average daily exposure to tobacco tar for men was 204 mg and for women 157 mg. Occupational and educational status were inversely related to the prevalence of smoking. The most popular packet size was 25 (preferred by 48% of smokers) and those in lower occupational and educational categories were more likely to purchase cigarettes in large packet sizes. CONCLUSIONS: Comparison with an earlier series of studies commenced in 1974 showed that the national prevalence of smoking among adults has continued to fall, particularly among men.