A recent consensus has emerged that proportionality can be applied with varying intensity depending on the subject matter of the challenged decision, which supports the use of proportionality as a general ground of common law review. That general consensus, however, should not be accepted without qualification, because it is only partially correct. Proportionality can vary in its application, in that the ease with which it can be satisfied depends on the facts. However, wherever it applies, proportionality must be pitched at the same justificatory standard, which requires courts to reach independent conclusions that executive decisions are suitable, necessary, and fairly balanced before finding them valid. This account of proportionality-which I call proportionality as epistemic independence is supported by the case law, is required for proportionality to provide a consistent benefit above and beyond Wednesbury, and avoids doctrinal over-expansion and incoherence. As a result, the question of whether and when courts should engage in proportionality review remains live.