From its inception, the Robert Wood Johnson Foundation (RWJF) has been driven by a continuous cycle of research, evaluation, and learning. RWJF continues its commitment to developing the evidence base by establishing four signature research programs - Evidence for Action (E4A), Health Data for Action (HD4A), Policies for Action (P4A), and Systems for Action (S4A). Together, these programs examine the factors necessary to build a Culture of Health by supporting the generation and dissemination of evidence about what works to improve population health, well-being, and racial equity.