Poverty Reduction Strategy Papers (PRSPs) have become key defining documents for economic and social policy in low-income countries since they were introduced five years ago by the International Monetary Fund and the World Bank. When they work well, PRSPs have the potential to enable civil society organisations to influence government policy in tackling poverty. This paper outlines Save the Children’s experience in facilitating children and young people’s participation in PRSP processes, arguing that they can make a significant contribution within this vehicle to developing effective strategies to tackle poverty. The paper highlights experiences from Vietnam and Honduras, and draws on insights from Lesotho, Bosnia and Herzegovina and the work of a Guyanese NGO. It explores the difficulties and challenges of involving children in such a process and discusses the effectiveness of a range of approaches and outlines learning points, raising questions about the impact and cost- benefit trade off of children and young people’s participation in PRSPs. Lessons emerge from Save the Children’s experience in this area, lessons which also relate to the experience of children and young people’s participation in policy-making generally, about what contributes to effective participation. Conclusions include: children and young people need to be well informed about the opportunities for influencing PRSPs; effective participation takes considerable time; feedback needs to be given; the ost marginalised children need to be included; cnsideration needs to be given to compensating children for the cost of their involvement; it is important to work with adults too; and partnerships need to be developed to share expertise.