Article 24 OECD Model Convention is a fundamental provision in every tax treaty. It contains several criteria which may not be taken as a basis for discrimination. A contracting state may not discriminate against foreign nationals, against permanent establishments of non-resident taxpayers, against payments made to non-resident enterprises, or against resident enterprises which are controlled by foreign enterprises. This course analyzes the concepts and implications of each non-discrimination clause, the interdependences of the non-discrimination clauses among themselves, and the interactions with distributive rules.

Withholding taxation is a central instrument through which states secure source-based taxation of cross-border income, and it lies at the intersection of domestic tax law, tax treaty law, EU tax law and international anti-abuse standards. Taking as its starting point the treatment of outbound and inbound payments under domestic law and bilateral tax treaties, the lecture aims to provide the conceptual and doctrinal foundations for understanding withholding taxes in an international and European context. It discusses the allocation of taxing rights over dividends, interest, royalties and other cross-border payments, the operation of treaty limitations on source-state taxation, and the practical significance of relief at source and refund procedures. Particular attention is given to the impact of EU law, including the fundamental freedoms, the Parent-Subsidiary and Interest-Royalties Directives, and the Court of Justice’s case law on discrimination, restriction and abuse. The lecture also addresses the role of beneficial ownership, anti-abuse doctrines, treaty shopping, and recent developments concerning administrative cooperation, transparency and enforcement. On the one hand, the lecture is intended to provide an introductory framework for more specialised lectures on international and EU tax law; on the other hand, it seeks to develop an understanding of how withholding taxation connects substantive taxing rights, procedural mechanisms and anti-abuse principles within the broader architecture of cross-border taxation.