Co-management is often put forward as a way to foster sustainability and improve the adaptive capacity of small-scale fisheries. Transformations towards co-management are enabled by processes that support social change, such as nurturing leadership, collective action and learning, as well as political processes that change legislative frameworks from centralized to decentralized decision-making. However, major policy changes can be difficult and change-actors often fail to overcome barriers created by institutional friction, dominant policy discourses or powerful interests supporting the status quo. In the literature, special attention has been paid to social processes that foster cooperation, the role of bridging-actors on the path towards co-management, or conditions that influence its effective implementation. In this paper we shift the attention to political decision-making and changes in policy discourse as an integral part of fisheries’ transformations. We use the well-studied cases of co-management transformations in small-scale fisheries to identify how interactions among political actors and stakeholders, as well as social-ecological interactions, shaped the policy discourse and influenced policy change during the transformation process. By comparing how policy change emerged across four fishery transformation cases, we illustrate the importance of (cross-scale and cross-type) coordination and collaboration among diverse political actors in creating conditions for adoption of legislation, as well as its timing during the policy process. The paper contributes to the literature on sustainability transformations by explaining how policy changes supporting such transformations may emerge, in addition to providing insight on political conditions and processes that could be fostered in order to support policy change towards decentralization in fisheries.