The goal of this proposal is to reduce the prevalence of chronic lung disease and other cigarette related illnesses through a smoking cessation program integrated into the prenatal care provided to a low income population. The major objectives of this proposal are: 1) to reduce the prevalence of cigarette smoking among women during prenatal care; 2) to reduce the incidence of smoking relapse during pregnancy among women who stop smoking prior to their first prenatal visit; and 3) to reduce the incidence of smoking relapse after the baby is born. Smoking cessation and relapse prevention advice will be given by physicians supported by more specific advice and counseling provided by smoking cessation counselors. The smoking cessation advice from the physicians will be tailored to the woman's level of intentions to stop smoking during the pregnancy. The smoking cessation counselors will work out plans to quit smoking, rehearse necessary skills and provide supportive materials. Physicians' advice and counselor support will be provided at each of the first three prenatal visits. The counselors will provide additional contact by phone, mail and home visits between the regular clinic visits. Further efforts to promote smoking cessation or to maintain abstinence will be made a the 36th week of pregnancy. Smoking behavior will be assessed by self-report and urinary cotinine at entry to the study and at the 36th week and by self- report and salivary cotinine three months after delivery. Exhaled carbon monoxide concentration, measured at prenatal visits, will provide an indication of smoking behavior for the physicians to use to provide feedback at these times. This project will draw on our skill and experience in patient education, behavioral approaches to smoking cessation, physician training, and program evaluation.