Port cities around the globe are developing different projects to reduce the negative externalities of port activities. In Spain, the port of Valencia just received the government approval to build an electric substation with a capacity of 30 Megawatts, giving a first step towards its goal of becoming a carbon-free until 2030. Also in Spain, the port of Barcelona has launched a free sustainability consultancy service for its end costumers, helping them know the emissions of logistic chains and facilitate the decision making towards greener transportation. Other promising field of study is blue carbon, or the process by which marine plants capture carbon and transfer it into sediments. The port of Seattle (USA) will collaborate with Washington State departments to study the benefits of this procedure. Finally, another way to reduce the polluting emissions is to avoid them at all, supporting carbon-free transport, such as wit, like the port of Le Havre is doing in the project TOWT – Transport à la Voile.