Smoking cessation during pregnancy remains an elusive public health goal. For poor and undereducated women, smoking may not be a priority in light of other pressing life issues. The proposed research evaluates the role of outreach health nurses in delivering a novel smoking intervention to poor, high-risk pregnant women. The smoking intervention will be conducted in the context of the Healthy Baby Program (HBP), an innovative community based outreach program that addresses basic life needs and medical care issues for pregnant women. A quasi-experimental design will evaluate the impact of a motivational intervention delivered via a well-established resource to reach women who would not typically present themselves for smoking interventions. A home visitation model will be used to deliver motivational and skills- based intervention components designed to increase women's awareness of smoking's impact on the fetus, their own health, and their household environment. The motivational intervention includes measurement and personalized feedback about the woman's pulmonary function and carbon monoxide, her household nicotine concentration, and linkages to the health care system. The control group receives usual care, as currently delivered by the HBP staff. Both groups will be followed for 12 months post- partum. The primary outcome is reduction in 7-day point prevalence smoking status. Secondary and intermediate outcomes include reduction in household nicotine concentrations, movement in stages of change, and smoking cessation attempts. Results will test the outcome and cost- effectiveness of a motivational intervention delivered via an existing social service program.