Over the last few decades many efforts have been made to address education issues through policy at various levels. Looking at these efforts around the world suggests that they have often been motivated more by beliefs than by evidence of impact. Not only are the wrong policies often adopted, but effective implementation of education policy is often lacking. In part this is because governments face particular constraints on what they can do. Education reform efforts would be stronger if they gave more attention to reliable research evidence and a greater focus to what is known about effective teaching.