The effect of different follow-up programs reinforced or not reinforced with the nicotine chewing gum Nicorette was tested by 13 physicians working in the open health care system. A total of 151 patients were advised to stop smoking, and were asked to participate in the program if judged sufficiently motivated by the physicians. After inclusion they were randomized into short or long follow-up, and nicotine gum vs no gum. The physicians conducted the follow-up therapy in their own personal way. Short follow-up was comprised of one appointment 14 days after cessation, while long follow-up consisted of a telephone call (1 week), an appointment (2 weeks), a second appointment (1 month), and a letter (3 months). The results at 12 months were that long follow-up showed a trend (P less than 0.12 toward being better than short follow-up, while nicotine gum was significantly better than no gum (P less than 0.05) in maintaining abstinence. The group with the best outcome was the one receiving long follow-up and nicotine gum, which yielded an expired air carbon monoxide-controlled, 12-month abstinence rate of 27%. The abstinence outcomes at 12 months for the other groups were short follow-up and nicotine gum, 22%; long follow-up and no gum, 15%; and short follow-up and no gum, 3%. The physicians' reactions to the smoking cessation treatment were largely positive. The nicotine gum seems to be a relatively simple, cost-effective, and practical tool for physicians to enhance and reinforce their antismoking advice. With a longer active follow-up period than was used here (1 month), even better results may be possible.