The efficacy of physician anti-smoking intervention with 289 patients in a family practice setting was assessed. The design included two treatment conditions, physician advice and physician advice plus the offer of nicotine chewing gum (NCG) prescription. A no-advice group permitted assessment of the effects of repeated testing. The NCG group had higher rates of abstinence at all follow-up points, but the difference approached statistical significance at 3 months only (p less than .10). Comparison of those who actually used NCG to all other groups revealed significantly more users were abstinent at 1- and 3-month follow-up. A similar pattern occurred for proportion attempting cessation and smoking reduction. A dose-response relationship of gum use to outcome was identified. Long-term users (greater than 20 days) had 86% abstinence at 3 months versus 18% for short-term users. Thus, NCG does appear to have a role in family practice for promoting short-term cessation.