This article explores efforts to bridge multi-disciplinary research and policy engagement to tackle child poverty in the contexts of developing countries, based on the experiences of Young Lives, an international longitudinal policy-research project. It focuses on a case study involving the application of research evidence on child poverty to shape policy debates concerning Ethiopia's second-generation Poverty Reduction Strategy Paper (2006-2010). The discussion is situated within theoretical literature on the interface between knowledge, policy, and practice, which supports the conceptualisation of policy making as a non-linear dynamic process. It pays particular attention to the importance of understanding the political and policy contexts of Southern countries, rather than assuming that they should simply import Northern-derived models of advocacy. It concludes by identifying general lessons for translating research into social-policy change.