Article 102 of the Treaty on the Functioning of the European Union (TFEU) prohibits the abuse of a dominant position within the internal market or in a substantial part of it, as incompatible with the internal market, insofar as it may affect trade between Member States. This essay examines the constituent elements of the prohibition found in Article 102 TFEU. These elements are: (i) one or more undertakings of a dominant position within the internal market or in a substantial part of it; (ii) effect on trade between Member States; (iii) abuse.