The work of Pierre Janet has experienced a “revival” recently particularly in what pertains to the effects of traumatic experiences and dissociation, or the discipline of Psycho-traumatology. Through his work with traumatized patients, Janet described phenomena like “fixed idea,” somnambulistic states, psychic and somatic automatisms, as well as psychic and somatic dissociative states. These would include somatic presentations of experiences, traumatic memories, and repressed emotions, also called “functional” or conversion disorders manifested in various organ systems. These included states like catalepsy, non-epileptic seizures, and other movement disorders. Psychic dissociation included psychogenic amnesias, fugue states, and multiple states of self. We conclude with the psychotherapeutic strategies used by Janet, still valid, and with the implications for the general treatment of these conditions.