This book explores the adaptation process of the General Agreement on Trade in Services (GATS) to a constantly changing trade and policy context. The adoption of the General Agreement on Trade in Services (GATS), a multilateral agreement with stand-alone rules and principles for the governance of trade and investment in services, represented a watershed in the history of global trade governance. Over three decades after the drafting of the Agreement, WTO Members struggle to deliver on the GATS’ mandate to achieve progressively higher levels of trade liberalisation in a radically different trade and policy landscape. Against this background, this book examines the contribution of the WTO negotiating, adjudicative and deliberative functions to adapting the GATS to changing circumstances. The book uncovers an extremely flexible and adaptable agreement whose full potential has yet to be realized due to a complex set of factors weighing more broadly on the WTO’s negotiating, adjudicative and deliberative functions. The book distils the factors at play that constrain WTO Members’ capacity to adapt the Agreement to changing circumstances, and explores potential pathways to overcome them. The book will be of interest to scholars, policy makers and trade diplomats interested in understanding the factors and processes conditioning the adaptation of a multilateral trade agreement to changing trade and policy circumstances.