Politicians have a different perspective on performance than the perspective implied in the NPM model. Political and economic rationality generate divergent objectives. Previous research has come to rather sceptical conclusions about the acceptance and use of performance information by local politicians. This dissertation attempts to answer the question of how important performance information is for local politicians in their daily policy-¬¬ and decision- making role. The research builds on empirical findings and attempts to evidence the presupposed patterns of use. We particularly focus on politicians’ assignment as policymakers in the administrative context of municipalities. Combining different dimensions (e.g. social, cultural, political) in the analysis of change processes the institutional framework will be used in searching answers for the discrepancy and the paradox between intended and actual use in practice of performance related documents. Institutional theory, sociological institutionalism and ter Bogt’s and Van Helden’s framework for studying organisational change might provide a basis to explore and analyse the reasons for using NPM like instruments in public sector organisations and their effects (ter Bogt, 2008a: 217). Data are collected from the Flemish city councils official reports completed with case and field study research. Preliminary findings suggest that the status of performance information in municipalities is still very precarious.