For almost every type of ship-generated waste, there is a variety of waste flows and on-board treatment methods. Studies show that ships use different treatment methods and often only treat part of a waste stream. This results in a difference between the amounts of waste generated and the amounts landed, indicating that measures, such as for example IMO’s obligatory Garbage Management Plans, fall short of sustainable and operational efficiency. The fact that IMO is encouraging voluntary cooperation between ports and shipping sectors to solve such problems indicates the urgency in developing the legislator framework of waste management, amongst other issues plaguing the shipping industry. This paper is part of a broader insight into ship generated waste, and addresses the existing legislation pertinent to waste management on ships and the role of ports. In this respect the European institutional framework is presented in addition to IMO Conventions and regulations. The Greek legislative framework is also studied, in an attempt to highlight possible novel contributions to the ongoing debate.