An analysis was conducted of the What Works Clearinghouse (WWC) research evidence base on the effectiveness of replicable education interventions. Most interventions were found to have little or no support from technically adequate research studies, and intervention effect sizes were of questionable magnitude to meet education policy goals. These findings painted a dim picture of the evidence base on education interventions and indicated a need for new approaches, including a reexamination of federal reliance on experimental impact research as the basis for gauging intervention effectiveness.