This second edition of the award-winning volume from Professor Duncan B. Hollis provides a comprehensive guide to treaties, shedding light on the rules and practices surrounding the making, interpretation, and operation of these instruments. Foundational issues are covered, from defining treaties and their alternatives, to examining current theorizations about the treaty in international law. Chapters review specific stages in the treaty's life-cycle, including formation, application, interpretation, and exit. Special issues associated with treaties involving the European Union and other international organizations are also included. A section sampling over four hundred actual treaty clauses complements these scholarly treatments. These real examples help illustrate different approaches treaty-makers can take on topics such as entry into force, languages, reservations, and amendments.