In this paper we describe the development and history of the KEEP (Keeping Foster Parents Trained and Supported) foster parent training intervention. The KEEP intervention represents a modified version of the Treatment Foster Care Oregon (formerly Multidimensional Treatment Foster Care) intervention developed by interventionists at the Oregon Social Learning Center and is designed to provide training and support for children ages 5 to 11 in regular foster care. We also report on the initial findings from a program of research focused on determining the effectiveness of the intervention. Thus far, the results indicate that the intervention is effective in reducing child behavior problems and that the effects of the intervention are mediated through changes in parenting behavior. There is also evidence that the KEEP foster parent training intervention increases the chances of a positive change of placement (e.g., child reunited with biological parents) and mitigates the negative risk-enhancing effect of a history of multiple placements. We conclude with a discussion of unanswered questions and directions for future research.