This project will be conducted to compare product use patterns and biomarkers of exposure between smokers who are assigned to a) gradual reduction in reduced nicotine content (RNC) cigarettes; b) immediate reduction to very low nicotine content (VLNC) cigarettes or c) normal nicotine content (NNC) cigarettes. The outcomes from this study will provide information on different approaches to reducing levels of nicotine in cigarettes and will determine the approach with the most optimal outcomes taking into account the balance between overall risk reduction (possibly maximized by abrupt switching) and compliance and acceptability (possibly maximized by gradual reduction of RNC cigarettes).