Abstract The attributed sui generis character of the EU as a polity has often been cited as the basis for not applying a classic separation of powers analysis to it. Yet it is a logical non sequitur to infer the inapplicability of a separation of powers framework to the EU on this basis: no particular proposition of political or legal morality can be automatically inferred or excluded from the attributed generic novelty of the EU relative to States. The EU certainly has some novel features, but that observation of itself does not establish that such novelty requires an entirely new conception of institutional normativity (rather, it needs to be explained how whatever particular novelty the EU possesses is such as to require the exclusion of separation of powers thinking). This article argues that a separation of powers analysis is: first, descriptively accurate, to a large extent, for much of the working of the EU apart from the law-making role of the ECJ; and, secondly, normatively attractive as a means of practically safeguarding the principles of democracy and the rule of law. This view is supported by an analysis of the substitute for a separation of powers in the caselaw of the ECJ, namely the principle of institutional balance, which it is argued is too vague and indeterminate to be a satisfactory alternative.