In considering unmarried parents, there are also two things we do not know: whether interventions to improve relationship dynamics might be successfully designed and implemented, and what effects they would have on unmarried couples and their children. This paper describes three studies sponsored by the U.S. Department of Health and Human Services, Administration for Children and Families (DHHS, ACF), designed to answer these questions. The first study developed a conceptual framework that identified the factors to be considered in the design, implementation, and evaluation of programs for unwed parents. A subsequent study focused on the implementation of such programs in the field. The third is a large-scale project that will help develop and then rigorously evaluate multiple programs that are based on a common research-based model for strengthening the relationships of unwed parents and supporting healthy marriage for those who choose it (Author abstract).