Who shapes policy mixes in sustainability transitions? Types of policy entrepreneurship and mechanisms of institutional change

Policy mixes—strategic combinations of policy objectives and instruments—are crucial for addressing complex societal challenges in sustainability transitions. Yet, how their characteristics—such as consistency, coherence, and credibility—emerge, and who shapes them remains unclear. This study poses the question: what role do actors play in shaping the characteristics of policy mixes? By integrating a co-evolutionary framework of policy mixes with a typology of policy entrepreneurship, we trace cycling policies in two Dutch cities using documents, reports, news articles, and interviews. Findings show that political entrepreneurs strengthened political credibility, problem brokers aligned policy objectives with societal needs, and process brokers improved coherence between policymaking and implementation, jointly enhancing policy effectiveness. We formulate propositions that clarify the role of different types of policy entrepreneurship in shaping policy mixes, contributing to research on policy mixes and the role of actors in sustainability transitions.