In summer 2013, a new Penal Code came into force in Iran, the first permanent one of its kind, as all previous reforms had been temporary measures. This chapter analyzes some characteristic features of the new 2013 code, particularly with regard to their sources and their effects. While rules in the areas of hadd, qesās, and diyeh are regarded as divine law that cannot be altered or abolished, they have been subject to interpretation, and Iranian Islamic legal scholars often restrict the applicability of hadd, partly by relying on minority opinions in legal justification. Furthermore, the 2013 Penal Code embeds hadd, qesās, and diyeh in other rules of substantive or procedural law in such a way that punishments can be diminished while formally remaining true to Islamic legal traditions. This is done, for example, concerning criminal responsibility of juveniles, and in the law of evidence. The chapter reviews the many adjustments and reforms undertaken in the Islamic Republic’s history to thoroughly Islamize its criminal law.