Despite considerable public and media concern, little attention has been devoted to prevention or early detection of substance use during pregnancy. A limited literature suggests that this lack of attention stems from a lack of policies or procedures for systematically identifying substance-using pregnant women and substance-exposed neonates in health care institutions. This study was designed to generate exploratory data about health care provider response to prenatal substance exposure and to examine current substance detection policies and practices in health care institutions. Based on interviews in local hospitals, study data reveal many disincentives to detecting substance exposure. For the most part, detection policies are not being developed or implemented, although hospitals serving poor communities are more likely to have such policies. Policy implications are discussed, including the appropriateness of mandated detection policies and whether such policies should be developed at the state or federal level.