 Any theory of criminal law must explain why criminal law is distinctive—why it is a body of law worthy of separate attention. This entry begins by identifying features of criminal law that make this so (§1). It then asks what functions that body of law fulfills (§2), and what justifies its creation and continued existence (§3). If criminal law should be retained, we must consider its proper limits (§4). We must consider the conditions under which agents should be criminally responsible for whatever falls within those limits (§5). And we must ask which rules of procedure and evidence should govern efforts to establish criminal responsibility (§6). The focus of this entry is Anglo-American criminal law and scholarship thereon. Many of the questions raised, and many of the answers considered, are nonetheless of general application.