This chapter considers the psychological connection between the person who commits the offense and the person who is being punished. Although a defense of any theory of personal identity would require its own monograph, we suggest that there is particular promise in those views that disambiguate questions of metaphysical identity from the kind of personal identification with the commission of the offense that matters normatively. We then try to taxonomize the different sorts of identity defenses as they fit within the extant criminal law’s structure. From there, we consider dissociative identity disorder and discuss different approaches to determining how many persons inhabit a single body, ultimately siding with the view that there may be no moral agent inhabiting that body. We also consider how different approaches should view “integration,” the form of therapy where the host and alter-egos (“alters”) are merged.