This practice piece will present a comparative reflection of how the use of evidence in policy looks when viewed from the outside, as a researcher, with how evidence use is experienced when working as a policy maker. The three authors are unusual in sharing an experience of studying evidence use in policy before becoming elected politicians who are involved in policy making and who have therefore gained a very different, more direct experience of how evidence is used in policy-making settings. Synhaeve has studied evidence use in secure youth care and is an elected councillor and was elected national member of parliament for the Democrats 66 Party in the Netherlands, McMahon has studied evidence use in public health and is an elected councillor for the Labour Party in England, while Heap has studied evidence use in social security policy and is an elected councillor for the Green Party in Scotland. The practice piece will consider to what extent their perspectives on evidence use in policy have shifted as they have moved from researcher to political representative and policy maker, and will consider to what extent these experiences have been shaped by their substantive policy interests and the political systems in which each is operating. It will conclude by summarising the collective insights that have emerged for the three authors as they have shifted to viewing evidence use from the perspective of an insider, who is using evidence in making policy, rather than an outsider, producing evidence with a view to influencing policy.