Adolescent pregnancy is a major social issue resulting in significant risk for both the infants and young mothers. In this paper, we will describe the effects of an intervention program for adolescent mothers and their infants, including the complexities of evaluating the effects of intervention for risk groups. More than half of the teenagers in the United States are sexually active, and more than 1.1 million become pregnant each year. It has been estimated that in 1981 approximately 22% of sexually active teens 15-19 experienced a pregnancy (Hofferth 1984). Among teen pregnancies, 70-80% are unintended and unwanted (PPFA 1984). Adolescent mothers and their infants appear to be at higher risk than older mothers for a variety of medical complications that may affect subsequent infant health and may impact on infant development and parent-infant interaction. While a number of studies have indicated that the biomedical risk for teenage mothers, especially those ages 15 and older, can be decreased considerably with adequate nutrition and proper prenatal care (Carey et al. 1983; Osofsky 1968; Osofsky and Osofsky 1970), for a variety of reasons, most teens do not receive the type of prenatal care that would most likely minimize risk and optimize outcome. Adolescent mothers are more likely than their nonpregnant peers to have lower education attainment, lesser job and economic success, and less frequent marital stability (Furstenberg 1976; Simkins 1984).