OBJECTIVES This paper examines differences between joiners and nonjoiners of a voluntary smokers' registry. METHODS A baseline prevalence survey was used to identify characteristics of smokers who joined or did not join a smokers' registry. RESULTS Communities varied significantly in registry enrollment rates. Heavy-smoking joiners expressed more desire to quit, were more likely to live with nonsmokers, and were older than nonjoiners. Light-to-moderate joiners smoked more, were more addicted to cigarettes, and expressed more desire to quit than nonjoiners. CONCLUSIONS Few baseline characteristics differentiated joiners from nonjoiners. Nonjoiners were significantly more likely to achieve cessation than joiners.