We compared the relative effectiveness of four different conditions of self-help and social support provided to people attempting to quit smoking in conjunction with a televised cessation program: Smokers ready to quit were able to request written manuals from hardware stores to accompany a televised program. At worksites we provided the written manual to all workers. At a random half of the worksites, we also provided training to discussion leaders who subsequently led discussions among smokers attempting to quit with the program. At health maintenance organization sites we invited smokers who had requested program materials to participate in similar group discussions at health centers. In this paper we report one year follow-up results for the above four groups and compare them with previously reported results of a self-help manual alone. Results for the television plus manual condition were better than those of past studies (25 percent nonsmoking prevalence and 10 percent continuous cessation one year after the program) and considerably better than the manual alone. None of the other conditions designed to supplement the manual plus television produced better long-term outcomes; we explore the reasons for this. The program did encourage and help over 50,000 Chicago smokers to attempt quitting with the American Lung Association manual, 100 times as many as would have done so without the televised program. At least 15 other similar programs implemented since 1984 multiply this effect.