Comparative education has traditionally meant the study of national education systems. But how far is this approach valid today? Doesn't the 'decline' of the nation state make national systems obsolete? Isn't the very idea of a 'system' anachronistic in a world of market triumphalism and global disorganization? The purpose of this article is to explore how globalisation is changing education and the implication of this for comparative study. Why study education systems and why study national education systems in particular? What else should comparativists study, and how? What defines the field of comparative education? These questions are approached first historically and secondly methodologically.