This report integrates the findings of five years of research and evaluation conducted by Operations Research and Impact Evaluation (ORIE) on the Working to Improve Nutrition in Northern Nigeria (WINNN) programme. The purpose of the report is to provide a high-level summary of WINNN’s achievements during the period of the evaluation (2013- 2016), as well as an overview of the key messages and recommendations that emerge from ORIE’s research. This is done with reference to the Organisation for Economic Co-operation and Development/Development Assistance Committee (OECD/DAC) evaluation criteria (effectiveness, impact, sustainability, efficiency and relevance).