This paper contributes to the discussion of evaluation use. It argues for a social practice approach to the analysis of evaluation use which enables a discerning and fine grained understanding of how evaluations might be used by real people in real time. It suggests a distinction between two dimensions of the way an evaluation might be used. It offers an interpretation of ‘use’ which focuses on the context and the capacity of the organisational setting in which evaluation outputs are used on the one hand and the other, is ‘usability’ which emphasises the extent to which the evaluation design itself militates against or encourages the use of its outputs in the broadest sense. The two dimensions are distinct yet closely inter-related. The paper concludes with a consideration of various approaches and tools which highlight the dimensions of use and usability from a social practice perspective.