We propose a double-blind, placebo-controlled, outpatient study with a between-groups design. Seventy-two male and female smokers will be randomly assigned to one of the 3 treatment conditions: GAL (8 or 16 mg/day) or placebo. The dose of GAL will be gradually increased to the target doses over a 2-week period (Table 2). During Week 3, following overnight abstinence from smoking, participants will present for a laboratory Test Session in which they will have the option of cigarette self-administration. After this Test Session is completed, smokers will be maintained on their randomized medication condition for an additional 4-week period. Smokers will establish a quit date at the beginning of this Treatment Phase, and will receive brief weekly behavioral treatment for the 4 weeks of this phase. Additionally, at the beginning of Week 3, participants will be given a PDA that will administer EMA assessments. The study medication will be tapered after the end of Week 4 of the Treatment Phase. Participants will be contacted by phone at one week, and one month, after treatment termination to inquire about any adverse events and about their recent smoking status.