Abstract: An American nondelegation doctrine is flourishing. Contrary to the standard account, it does not forbid Congress from granting broad discretion to executive agencies. Instead it is far narrower and more targeted. It says, very simply, that executive agencies cannot make certain kinds of decisions unless Congress has explicitly authorized them to do so. In so saying, the American nondelegation doctrine promotes the central goals of the standard doctrine, by preventing Congress from shirking and by requiring it to focus its attention on central questions, and also by protecting liberty. The abstract idea of “certain kinds of decisions” is currently filled in by, among other things, the canon of constitutional avoidance; the rule of lenity; and the presumptions against retroactivity and extraterritoriality. More recent nondelegation canons, not yet firmly entrenched, require agencies to consider costs and forbid them from interpreting statutes in a way that produces a large-scale increase in their regulatory authority. The cost-consideration canon makes a great deal of sense, especially as a way of disciplining the modern regulatory state; the “major questions doctrine,” as it is sometimes called, is less obviously correct. and its proper provenance depends on the nature of the relevant statute.