Critics often charge that Kantian ethics is implausibly rigoristic: that Kantianism recognizes a set of perfect duties, encapsulated in rules such as ‘don’t lie,’ ‘keep one’s promises,’ etc., and that these rules apply without exception. Though a number of Kantians have plausibly argued that Kantianism can acknowledge exceptions to perfect duties, this acknowledgment alone does not indicate how and when such exceptions ought to be made. This article critiques a recent attempt to motivate how such exceptions are to be made, (...) namely, the constitutive approach developed by Tamar Schapiro. I argue that the constitutive approach is vulnerable to the objection that it is too permissive, justifying many morally dubious exceptions to perfect duties. I conclude by briefly outlining an alternative ‘fine print’ approach to the rigorism objection that appears to avoid the objection leveled at Schapiro’s approach, focusing on how modifying the constituents of agents’ maxims can change the deontic status of an act of a generally impermissible kind. (shrink)