To date EU anti-discrimination legislation, particularly the Employment Equality Directive (Directive 2000/78/EC), does not provide any clear definition of disability as a ground of discrimination. In the last few years, the Court of Justice of the European Union (CJEU) has attempted to fill this gap and discussed the concept of disability in several decisions, in the attempt to provide a definition of the ground of disability. The ratification by the European Union of the UN Convention on Rights of Persons with Disabilities (UNCRPD), has led to a clear overruling in the case law: the Court shifted from the medical model to the social model of disability. The UNCRPD now represents a milestone for the CJEU, which recognised that a duty arises to define disability in line with the social model, under the principle of consistent interpretation. Against this background, this article discusses CJEU case law, and compares and contrasts the judicial activism of the Court with the cautious approach adopted by the European Commission in the proposal for a new non-discrimination directive.