In what ways are experts involved in policy development, and with what results? This paper attempts to answer these questions through a structured review of the academic literature, focusing on the identification of ‘methodologies’ of expert involvement, and on analying the subsequent policy impact of those exercises. Coding was applied to 103 articles, revealing that only a small range of methods has been utilised, that method choice is infrequently justified, and with little evidence of evaluation (either of the expert involvement process or of policy impact). We argue that robust evaluative processes are necessary to refine the efficacy of involvement processes (and the accuracy with which involvement methods are aligned to specific types of policy questions) and to document policy translation of outcomes. We therefore propose a framework to identify appropriate consultation methods for specific policy questions, and suggest some criteria for reporting expert involvement processes in the future. Keywords: expert involvement; policy development; policy translation; stakeholder involvement; systematic review.