Many low income countries are off-track to reach the Millennium Development Goals for water supply and sanitation. This paper develops a theoretical framework and methodology to improve the evaluation of water and sanitation programme outcomes, focusing on relevance, effectiveness and sustainability. The resulting set of evaluation questions are applied to seven independent evaluations of WaterAid's country programmes. Results are synthesised by assigning an ordinal ranking to the findings which are aggregated to assess overall outcome status that has validity at an organisational level, rather than just at country programme level. Strong areas of performance are partnership development, policy advocacy, equity and inclusion. Areas requiring attention are organisational learning, programme structure and government partner capacity for sustainability. The findings will be used to prioritise future programme management and are clustered into seven outcome areas that are of generic interest and significance to other organisations managing water supply and sanitation programmes.