Ports and container terminals increasingly operate in ecosystems where rivalry and collaboration coexist. Shipping alliance consolidation, larger vessel sizes, port-hinterland integration, digital platform development, sustainability pressures, and recurrent disruptions have made purely competitive or purely cooperative models insufficient for explaining contemporary port strategy. This study redesigns the general coopetition concept for the maritime domain and develops an integrative framework for analysing coopetition in ports, container terminals, maritime logistics networks, and port competitiveness. The study adopts an integrative review approach that synthesizes three literature streams: coopetition and strategic management, port competition and competitiveness, and maritime logistics network governance. The findings show that port coopetition is most relevant where competitors share systemic interdependencies, such as capacity utilization, hinterland connectivity, digital information exchange, environmental compliance, security, safety, and resilience, while still competing for cargo, shipping line calls, investment, and market share. The proposed framework identifies five operational domains of port coopetition: strategic and institutional coordination, infrastructure and capacity sharing, operational synchronization, digital and information-based collaboration, and sustainability and resilience-oriented cooperation. It also highlights the main risks of coopetition, including opportunism, knowledge leakage, dependency, unequal bargaining power, regulatory concerns, and data governance failures. The study contributes to maritime technology and port management research by converting coopetition from a general strategic-management concept into a port-specific decision framework aligned with maritime transportation systems. Practically, the framework supports port authorities, terminal operators, and policymakers in designing governance mechanisms that balance value creation, fair competition, and system-wide resilience.