The confrontation between maritime transport and ecological transition raises colossal challenges. It questions both the technical system, able to respond to environmental issues, and the capacity of the socio-system to initiate adaptation dynamics. If the ship is often at the heart of the reflections to engage this green revolution of shipping, the role of the port in this transition appears more difficult to apprehend. Commercial ports, as interface spaces, offer ecology a system of flows that is complex to grasp as a whole. The port metabolism therefore calls for a necessarily interdisciplinary approach that this session intends to highlight.