In this chapter I restrict myself to exploring the nature of the amnesia which is reported between personality states in most people who are diagnosed with DID. Note that this is not an explicit diagnostic criterion, although such amnesia features strongly in the public view of DID, particularly in the form of the fugue-like conditions depicted in films of the condition, such as The Three Faces of Eve (1957). Typically, when one personality state, or ‘alter’, takes over from another, they have no idea what happened just before. They report having lost time, and often will have no idea where they are or how they got there. However, this is not a universal feature of DID. It happens that with certain individuals with DID, one personality state can retrieve what happened when another was in control. In other cases we have what is described as ‘co-consciousness’ where one personality state can apparently monitor what is happening when another personality state is in control and, in certain circumstances, can take over the conversation.