The institutionalization of evaluation within Italian public organizations has gained momentum thanks to the impulse of EU structural funds. Issues of evaluation institutional design are currently debated in scholarly political and organizational discourse on public management. This article explores how institutional forms and rules interact with evaluation-based knowledge in predictable ways that structures evaluation uses to change administrative processes and practices. We focus on the case of the World Bank where program evaluation has been institutionalized since the 1970s. The article addresses such issues as: (i) the independence of evaluation, and its legitimacy for decision making, (ii) the governance and accountability mechanisms, which evaluation may or may not reinforce, and (iii) the organizational values and culture that frame evaluation studies and underlie the perceived usefulness of evaluation for management decisions.