The Supreme Court of Canada’s decision in Dunsmuir was intended to rationalize and simplify its approach to standards of judicial review of administrative decisions. However, the various judgments in the case actually suggest a subtle but important shift in the focus of the Court’s review of the “reasonableness” of government decisions. Two contrary and potentially conflicting approaches to selecting and applying the standard of review are reflected. On the one hand, the decision indicates that where the question is one of discretion, “deference will usually apply.” On the other hand, the Court will also continue to apply the factors that went into what used to be called the “pragmatic and functional test” for standards of review: whether there is a privative clause, the expertise of the decision-maker, and the nature of the legal question. Further, even where “reasonableness” is the chosen standard, courts are now called on to go beyond reviewing the decision-making process for legality to determine whether the decision itself falls within a defined set of permitted, “reasonable” outcomes.The Court has adjusted the law with respect to judicial review of all types of government decisions, including those involving ministerial discretion. In consequence, the judgment does not take into account the important distinctions between ministers as decision-makers as compared to other tribunals, including the fact that Parliament empowers ministers when it intends the decision to be subject to political, not just legal, accountability, through the minister’s responsibility to Parliament. The application of the Dunsmuir approach in that context has the potential to affect the balance between the legal and political accountability of ministers, their ability to delegate to their officials, and the respective roles of the courts, the executive and the legislature in making and implementing policy.