The first future direction (which will be uniquely facilitated by the full sample of 560 EGDS adoption triads) is the disaggregation of genetic, prenatal drug exposure, and postnatal rearing environment effects on young children. The prospective adoption design provides unique leverage to this question in three ways: the postnatal environment is distinct from the prenatal environment, a child's genetic risk for substance use and maternal prenatal substance use can be classified, and the effects on the child can be examined prospectively. In studies of biological families, this fine-grained separation of postnatal, prenatal, and genetic effects cannot be achieved. This research focus will provide novel information on how the postnatal rearing environment enhances or reduces risk to children engendered by birth parent drug use and on whether this risk is conferred by genetic or intrauterine mechanisms or by an interaction between the two. Once the underlying etiological factors contributing to children's poor outcomes related to birth parent substance use have been more precisely identified, intervention programs can more adeptly target the primary causes leading to child risk. For example, if children
