The goal of this publication is to provide an accessible introduction to the scheduling functions of the Commission on Narcotic Drugs. It is intended for ease of reference only. To keep the explanations as understandable as possible, some aspects have been simplified. References to the three international drug control conventions and on those commentaries on those conventions have been limited in order to increase readability; section IV (“Useful resources”) provides weblinks to the full texts of those conventions and commentaries.