The report provides a reference for how microplastics may be addressed under a global agreement to end plastic pollution. It elaborates on how microplastics are currently regulated and managed, and potential measures and modalities to address microplastics. The report is intended to inform and inspire stakeholders and policymakers, including negotiators and delegates in the Intergovernmental Negotiating Committee (INC), to consider microplastics holistically.The report introduces key concepts and summarises the knowledge base and gaps that remain for a science-policy interface on microplastic pollution. It analyses existing measures on the regional and national level and shows how different measures are required to address various sources and pathways. A chapter is dedicated to lessons learnt from existing multilateral environmental agreements of relevance for microplastic pollution.