In this paper, we propose a conceptual framework for constructing a diffusion index of changes in overall perceptions with respect to corruption. The corruption diffusion index we construct lies between 0 (the greatest overall deterioration in corruption perceptions) and 100 (the greatest overall improvement in corruption perceptions) with 50 (no change in corruption perceptions) as the critical reference. The proposed methodology is applied to the 2010/2011 global corruption barometer survey data. Possible refinements of the proposed methodology to capture the potentially (...) multi-dimensional nature of corruption and the practical challenges associated with the empirical implementation are discussed. (shrink)