Voice, empowerment and accountability (VEA) interventions aim to support poor and marginalised people to build the resources, assets, and capabilities they need to exercise greater choice and control over their own development, and to hold decision-makers to account. This guide provides an overview of the best available evidence on the impact of VEA interventions. It identifies what we know about the barriers to VEA in different contexts, and emerging lessons on how to address them. Two main rationales for supporting VEA recuracross the literature. One is that voice, empowerment and accountability have intrinsic value, as objectives in and of themselves. A second rationale is that VEA is instrumental to the achievement of a broader range of development goals, including inclusive institutions, improved access to and quality of public services, and human development outcomes. VEA also aims to support inclusive political settlements in which states respond to the needs of all groups.Evidence of the impact of VEA interventions is limited and inconsistent–identifying both positive and negative effects. Only a small body of literature has analysed the (potential) role of VEA in supporting development goals, and the evidence is clustered around more measurable effects on service delivery, particularly health and education. Overall, the evidence consistently demonstrates that the impact of VEA depends on context: specifically, on pre-existing power relations, social norms, levels of equity or exclusion, leadership, and the capacity and will of both state and civil society actors.