In the past decade, the Government has repeatedly emphasised the importance of taking an 'evidence-based'approach to policy making. Since then, efforts to ensure that policy making is evidence-based have focussed largely on incorporating scientific advice into the policy process. Yet despite a growing recognition that evidence from the natural and social sciences can benefit policy, evidence from humanities disciplines such as history continues to have limited input into the policy process. As a consequence, there is a danger that opportunities to learn from past successes and failures are being missed. While historians and policy makers often agree that cooperation could be beneficial, uncertainties remain on both sides about how this might best be achieved. Historians often know relatively little about the policy-making process, while policy makers may doubt that past events can be relevant to present problems. This POSTnote aims to provide MPs and Peers with an outline of the potential benefits and limitations in using historical precedents to inform science and technology policy, including an overview of current practice in evidence-based policy making and suggestions for how current difficulties could be overcome.