Women frequently quit smoking during pregnancy but then relapse postpartum. The BABY & ME-Tobacco Free program combines prenatal and postpartum smoking cessation counseling and biomarker feedback with monthly postpartum incentives. The settings included 22 sites (WIC offices and prenatal clinics) in upstate New York. A quasi-experimental design was used to evaluate this intervention, that included four face-to-face prenatal sessions with a counselor who did smoking cessation counseling, carbon monoxide testing and random saliva cotinine testing. For 1 year postpartum, mothers were biochemically tested every 3-4 weeks and, if negative, were issued a voucher for diapers. Three implementation models were studied: multi-tasking counselors at fixed sites (Models 1 and 2) versus itinerant smoking cessation specialists (Model 3). Outcomes included biochemically validated abstinence rates during pregnancy and postpartum. Logistic regression was used to identify predictors of postpartum abstinence and program dropout. Proportional hazards regression was used to compare implementation models. Of the 777 pregnant women who enrolled in the program, 588 were eligible for the postpartum program. The intention to treat pregnancy quit rate was 60%. Postpartum, Model 3 showed consistently better quit outcomes than the other models. Predictors of abstinence at 6 months postpartum are: older age (OR = 1.07, 95% C.I. 1.02-1.12), lower baseline carbon monoxide level (OR = 0.69, 95% C.I. 0.49-0.97), Model 3 (OR = 4.60, 95% C.I. 2.80-7.57) and attending more prenatal sessions (OR = 3.52; 95% C.I. 2.19-5.65). The BABY & ME-Tobacco Free program is an effective smoking cessation program for pregnant and parenting women.