The use of impact assessment can be characterised on a scale with ‘proving impact’ on one side and ‘improving practices’ on the other. Even though this is not an either/or scale, the two often do not combine automatically. In this article an adjusted Sustainable Livelihood Framework for impact assessment is developed that does justice to both. The use of this framework has implications in terms of a multi-method research approach, an extensive variety of data collection, and an in-depth data analysis. This is illustrated by applying the framework to a socio-economic impact study conducted for the DE Foundation coffee support project.