This report is to provide legal guidance to COBSEA-member countries on tackling sea-based sources of marine liter. The main objective is to conduct a gap analysis and assessment of sea-based sources of marine litter related legal frameworks within the context of the issue in the East Seas region. The outcome is a set of recommendations on interventions at the regional level, and for the development and/or reform of laws and policies on marine litter (land and sea-based sources, and with a focus on plastics), to align with global efforts and best practices on the issue.