This yearbook brings together, in one volume, the texts of the most important Multilateral Environmental Agreements (MEAs), including the most recent texts of Rules of Procedure, Financial Rules, and Compliance Procedures. A short description of each MEA is given, including a fact sheet covering date of adoption, date of entry into force, parties, amendments, websites, and Convention of the Parties (COP) history. The 'Year-in-Review' gives an account of the most salient negotiating issues and developments in the year covered. The 'Year Ahead' section sets out what the key negotiating issues will be in the forthcoming year. This work provides a comprehensive and indispensable tool for the MEA legal practitioner.