The situation in California demonstrates that the Healthy People 2010 goal of 15% prevalence by 2010 is not only achievable in California, but surpassable. Indeed, it is possible to reduce smoking prevalence in California to 10% in five years. While prevalence has not been dropping, the percentage of light smokers (those who smoke less than 15 cigarettes/day) increased by 9% between 1996 and 1999, to 60% of all smokers.12 The fact that most smokers are light smokers will make it easier to reduce overall smoking rates as light smokers are more likely to quit than heavy smokers. The National Cancer Institute COMMIT trial, an experiment involving a cohort of 13 415 smokers from 20 US and 2 Canadian communities, showed that 40% of those who smoked fewer than 15 cigarettes per day had stopped smoking after 5 years compared to 21% who smoked 15 cigarettes or more.13 Applying these quit rates to California (where 60% are light smokers) corresponds to 24% of the light smokers quitting within 5 years. Therefore, approximately 30% of all smokers would be expected to quit within 5 years. If smoking initiation does not increase substantially, this effect would correspond to a decline in prevalence of 1.2% per year. Reaching a goal of 10% prevalence in California in 5 years only requires accelerating this rate to 1.4% per year.