This report reviews the effectiveness of the Knowledge Sector Initiative (KSI)’s support to 16 Policy Research Institutes (PRIs) over its two phases of operation, taking place between 2013 and 2022. The review focuses on four areas of support to PRIs: research quality; network and profile; engagement and influence and; financial sustainability. The review took place over four months between November 2021 and March 2022 and comprised the development of a ‘results note’ for each PRI drawing on a review of documentation, interviews with staff from every PRI and some interviews with policymakers. This report synthesises findings from the 16 results notes and (will) incorporate comments from three sense making sessions with staff from KSI, PRIs and DFAT. Asked about the most noteworthy changes to have emerged from their engagement with KSI, most PRIs highlighted improved organisational capacity in the form of planning and management processes, staffing, organisational infrastructure and financial sustainability. Then came better profile amongst, engagement with and influence of stakeholders, followed by better research quality stemming from improved methods and better integration of Gender Equity, Disability and Social Inclusion (GEDSI).