Recent Australian public law scholarship has demonstrated an increasing interest in the theme of constitutional values. In the current paper, I seek to clarify the terms of the debate by defending a distinction between (i) constitutional principles, understood as relatively flexible legal norms which rest on text, structure and history and (ii) extra-legal values. My argument is framed initially through a critical discussion of Rosalind Dixon’s proposal for a ‘functionalist’ approach to constitutional interpretation, which ascribes a central place to values in judicial reasoning. The functionalist position, I contend, lacks a sufficiently clear distinction between, on the one hand, constitutional principles as legal norms and, on the other, extra-legal values of political morality. As a consequence, the functionalist appeal to ‘constitutional values’ tends to shift between a relatively modest supplement to purposive approaches to judicial interpretation and a more ambitious proposal for judges to promote ‘normatively attractive’ values. These claims are elaborated and refined through a comparative analysis of German constitutional jurisprudence and a recent example of an appeal to values by the High Court.