Admissibility is a property of a formal criterion with respect to a normative theory. A given criterion is admissible with respect to a specific normative theory if (and only if) it abides by all the norms that underlie that theory. In particular, for a decision‑making criterion to be admissible with respect to decision theory, it must never allow the decision maker to willingly decrease his or her welfare for certain.

See also: Decision Tree and Money Pump.