This article describes our state of knowledge regarding the development and prevention of conduct problems in early childhood, then identifies directions that would benefit future basic and applied research. Our understanding about the course and risk factors associated with early-developing conduct problems has been significantly enhanced during the past three decades; however, many challenges remain in understanding the development of early conduct problems for girls, the contribution of poverty across variations in community urbanicity, and developing cascading models of conduct problems that incorporate prenatal risk. Significant advances in early prevention and intervention are also described, as well as challenges for identifying and engaging parents of at-risk children in nontraditional community settings.