In this study, we used institutional analysis to investigate the design of innovative contracts for agri-environmental and climate schemes. The aim of such contracts is to better incentivize farmers for the provision of environmental public goods in comparison to current 'mainstream' contracts. For the analysis, we differentiated four contract types: result-based, collective, land tenure, and value chain contracts. To represent each type in the analysis, we selected 19 case examples from six European countries. Cases were identified through a mix of methods, combining literature review, web search, and expert consultation. After a structured data collection based on Ostrom's institutional analysis and development (IAD) framework, we focused our analysis on the involved actors and their roles in contract governance. Our results highlight the great diversity of public, private, and civil actors involved from the local, regional, national or international governance level, each performing one or several critical roles in contract governance. We found that it is highly context-dependent which actors assume certain roles. We also discuss how provision of environmental public goods through the contracts might potentially be impacted by certain roles and their assignment to specific actors.