Delreux examines how the EU functions when it participates in international environmental negotiations. In particular, this book looks at the internal EU decision-making process with regard to international negotiations that lead to multilateral environmental agreements. By studying eight such decision-making processes, the book analyses how much negotiation autonomy (or 'discretion') the EU negotiator (the European Commission or the Council Presidency) enjoys vis-a-vis the member states it represents and how this particular degree of discretion can be explained.