Every year, millions of college students are referred to developmental courses (also called remedial courses). Success rates in these courses are low: Fewer than half of developmental students pass the course sequences to which they were referred. Being referred to developmental education is also highly correlated with dropping out of college. Colleges, researchers, and advocates across the nation have therefore identified developmental education as a place that innovation and change are needed. Research shows that many students referred to developmental education are underplaced. That is, they would have been successful if they had gone directly into college-level courses instead. States and colleges looking to improve student outcomes should start by figuring out which students do not need developmental courses at all. From there, states and colleges can look at other interventions to help students who do need additional support. MDRC is one of many research organizations evaluating innovations in developmental education. For more than a decade, MDRC and the Community College Research Center at Columbia University have together led national research centers on developmental education. This brief presents the latest research on developmental education and provides high-level summaries of findings and implications for practice for states and colleges interested in making a change.