Peace and security are fundamental for the resilience of Baltic Sea Region communities, especially in today’s complex geopolitical landscape. The war in Ukraine and hybrid threats like cyberattacks, disinformation, and maritime sabotage have exposed the vulnerability of coastal communities. A major concern is the shadow fleet: poor maintenance and illicit activities of unregulated vessels endanger marine and coastal ecosystems. HYBRIDGE aims to enhance the capacity of institutions to prevent and manage shadow fleet-related environmental threats. It addresses fragmented responsibilities among civilian, military, and environmental authorities that currently hinder effective action. HYBRIDGE will develop and implement a Peace and Security Innolab as a collaborative space for authorities, practioners and researchers for co-creating innovative solutions to hybrid maritime threats. At its core, the Innolab uses serious gaming scenarios to simulate real transnational operational challenges, improving institutional decision-making, coordination, and joint response capabilities. This approach helps identify and codify best practices in transnational and inter-institutional communication, responsibility clarification, and emergency coordination, thereby strengthening decision-making and improving access to up-to-date knowledge and research across national and sectoral boundaries to ensure swift, unified responses to maritime incidents that transcend jurisdictions.