The report is the result of research into the impact of children’s participation on development programmes and how such participation can be facilitated. It brings together the findings of a literature review of current thinking about children’s participation and its evaluation with a field study undertaken in three different countries (Ecuador, India and Kenya). It also focuses on the changes – both positive and negative – that children’s participation may bring about, and discusses various issues relating to evaluation. Possible tools and methods are described and consideration is given to the manner in which evaluation activities are conducted. The report considers the challenges for agencies in seeking to develop children’s participation further, and the introduction of a participatory approach to evaluation itself.