The most common disease in Korea is smoking and the number of the sufferers is about twelve million. The prevalence of smoking among doctors may indicate the likelihood of success of population-based anti-tobacco campaigns. It has been established that the decline in the prevalence of smoking among physicians has preceded the decline in the general population according to the Kunz's two-phase model in smoking epidemic. There is also evidence that physicians who smoke are less likely to counsel patients about the hazards of smoking. For these three reasons it is important to understand the current smoking status among medical doctors.