Belgian academic development units typically are located at the central level of universities.They work in close collaboration with academics and the vice-rector of education to whom they also report. Consequently, academic developers often find themselves involved in a power game, in which they try to reconcile their professional values with the demands from university administrators. This is illustrated by the case study of the implementation of a teaching portfolio as a developmental and evaluative tool at the Université Catholique de Louvain. The data regarding both the perceptions and actual practices of academics and the chairs of promotion commissions reveal that the different actors perceive and use teaching portfolios in a primarily summative way, notwithstanding the fact they all endorse its develomental value. Although the academic developers offer support to the academics in line with their professional values, they do not seem to play a major role of significance in their perceptions nor practices. These findings plead for an organisational model in which academic developers and the university administrators shift to a power model inspired by Montesquieu’s notion of the separation of powers. In the latter model academic developers and the university administrators might overcome the tension between compliance and resistance and open up new opportunities.