 Purpose: A pilot randomized double-blind placebo-controlled trial is testing the feasibility of conducting a full-scale trial of the efficacy of bupropion SR vs. placebo in non-breastfeeding postpartum women who smoked 1 cigarette in the last month of pregnancy and want to stop smoking. The study will estimate achievable enrollment and retention rates; estimate the effect size of the drug on tobacco abstinence; assess the tolerability of bupropion in postpartum women; and allow refinement of recruitment, retention, intervention, and assessment protocols. 