This research will determine whether two highly promising modifications to varenicline treatment (i.e. use of a nicotine patch adjuvant and extended 24-week duration) produce superior smoking outcomes when they are either used together or alone. Despite their promise, the proposed modifications have never been experimentally evaluated relative to standard varenicline pharmacotherapy. Thus, this innovative research will produce novel evidence regarding how best to help smokers quit, and thereby address the leading cause of preventable mortality and morbidity related to cardiovascular and pulmonary diseases.