This study examined treatment outcomes among smokers with single versus multiple behavioral risks. Data were drawn from smokers (N = 2,326) participating in 3 population-based, multibehavioral studies targeting cigarette smoking, high-fat diets, and high-risk sun exposure. Outcomes were compared for participants at risk for smoking only (13%), smoking plus 1 additional risk factor (37%), and smoking plus 2 additional risk factors (50%). The smoking only group tended to be female, older, more educated, lighter smokers, in the preparation stage of change for smoking, with more previous quit attempts and longer periods of abstinence. At 12 and 24 months follow-up, treatment of 1 or 2 coexisting risk factors did not decrease the effectiveness of smoking cessation treatment, and treatment for the coexisting factors was effective.