METHODS In this study, we will randomize 398 smokers with COPD to one of two treatment arms: 1) traditional smoking cessation (SC) or 2) long-term, guided maintenance therapy with NRT (GMT). Participants in the SC arm will receive a standard approach to smoking cessation, including smoking cessation counseling supplemented with combination NRT (nicotine patch plus choice of gum or lozenge) if they are willing to make a quit attempt. Participants in the GMT arm will receive counseling focused on medication adherence and smoking reduction plus 52 weeks of combined NRT. Outcomes will be measured at 3, 6 and 12 months post-randomization and will assess rates of smoking cessation, number of cigarettes smoked, exposure to carbon monoxide and smoking-related carcinogens, and clinical outcomes including respiratory symptoms, respiratory function, and smoking-related hospitalizations or death. In addition to directly comparing outcomes in the two treatment arms, our novel classification and regression tree analysis will allow us to identify subgroups of patients most likely to benefit from treatment and will allow patients to estimate their projected outcomes given their personal history and their choice of therapy.