Digitisation has significantly impacted international trade. This book explains the impact of digitisation on trade in services, the ensuing concept of 'digital services' and the different types of trade barriers these services face. This book establishes that the legal framework that applies to trade in services also applies to digital services. It elaborates on the scope of the General Agreement on Trade in Services (GATS) and how to classify digital services. The relevant GATS obligations are subsequently applied to several case studies that illustrate the barriers to digital services trade. These case studies demonstrate the impact of the applicability of GATS to digital services on countries' international obligations. Finally, the book maps the electronic commerce-related provisions in in regional trade agreements (RTAs). Six extensive e-commerce RTAs are compared in depth and it is considered whether they add substantially to the existing multilateral obligations applicable to digital services trade.