This paper employs the Institutional Analysis and Development framework across six ecosystem delivery measures in the European Union to develop a configurational explanation of (un)successful outcomes. By undertaking comparative institutional analysis, we systematically examine the effect of variation across rule types and generate insights on how different institutional configurations result in varying degrees of successful implementation of ecosystem delivery measures. We apply explanatory typology methods to identify the institutional features that best explain variation in implementation success across a number of cases. We argue that institutional rules shape outcomes in conjunction rather than in isolation. The findings show that differences in implementation success across cases can be explained by the interplay of differences in knowledge exchange, flexibility in implementation, and participation in the policy design process.