This guide is intended to help customs and border control officers in ensuring implementation of national legislation, transposing the agreements under the Green Customs Initiative (GCI), and thus promoting national compliance with those agreements. Chapter 1 explains what MEAs are and introduces the entities that are partners to the GCI. Chapter 2 provides an overview of the main international MEAs with trade related provisions, with details on how they regulate trade, the roles and responsibilities of customs and other border authorities, the specialized terminology associated with MEAs, and where to find additional information and guidance in this regard. Chapter 3 explores the practical aspects of implementing MEAs’ monitoring requirements, including: the identification and checking of suspicious items; seizure and disposal; health and safety; other legal issues; and cooperation with other authorities. This chapter also includes references to additional training and reference materials and other useful information.