We present accepted basic arguments on the role of institutions in development and then discuss the corresponding empirical evidence in support (or not) of those arguments. Methodologically, our emphasis is on experimental evidence wherever available, and thematically we focus on political and legal institutions. In the political sphere, we distinguish between rules shaping representation and accountability, and state capacity. In the legal sphere we distinguish between the profile of legally sanctioned rights (such as property rights and the role of informality) and the workings of the judiciary and the quality of enforcement. We distil the lessons learned from the literature and present open questions in each topic, thus highlighting promising avenues for future empirical research. Institutions matter for growth and inclusive development. But despite increasing awareness of the importance of institutions on economic outcomes, there is little evidence on how positive institutional change can be achieved. The Economic Development and Institutions-EDIresearch programme aims to fill this knowledge gap by working with some of the finest economic thinkers and social scientists across the globe. The programme was launched in 2015 and will run for five years. It is made up of four parallel research activities: path-finding papers, institutional diagnostic, coordinated randomised control trials, and case studies. The programme is funded by the UK Department for International Development. For more information see http://edi.opml.co.uk.