Coastal areas are increasingly exposed and vulnerable to environmental degradation and climate change, requiring adaptive governance approaches that integrate the climate–environment–health nexus. In Réunion Island, a French overseas department and EU region, two decades of science‐policy initiatives have aimed to improve coastal governance through stakeholder engagement, scientific knowledge integration, and deliberative processes. Building on the evolutionary governance theory framework, this study analyzes a body of 281 scientific research articles (2000–2024), 4 participatory projects (2005–2020), and 12 expert insights to identify land–sea governance challenges and opportunities. Scientific articles remain focused on diagnosing environmental problems rather than elaborating systemic solutions, with a predominance of ecological and conservation science. Participatory governance and long‐term strategic foresight are underdeveloped, and while digital tools are widely used for environmental monitoring, their integration into decision‐making remains insufficient. Key barriers include administrative fragmentation, weak institutional coordination, and difficulties in integrating scientific knowledge into policy processes. Four enablers emerge: strong political leadership, long‐term institutional support, a shared strategic vision, and regional cooperation aligned with European and international frameworks. Additionally, Réunion’s hybrid sociability, shaped by its colonial history, presents both challenges and opportunities for governance. While it may foster exclusivity, it can also facilitate trust‐based collaboration. A dedicated land–sea governance structure could enhance multi‐scale and multi‐level coordination among stakeholders.