Probably few leading psychiatrists today use or recommend the use of hypnosis as a psychotherapeutic technic. It is true, however, that dynamic psychiatry as now practiced owes its major development to the observations of Freud and other associated workers on hypnotized subjects. Posthypnotic suggestion made it possible for Freud to demonstrate the presence of the unconscious without any possibility of doubt. Working with hypnotic subjects, he was able to demonstrate also that it was possible to bring unconscious memories into consciousness. At the present time most psychiatrists believe that the use of sodium penthothal (or a similar drug) is just as efficacious as hypnotism and has the particular advantage of allowing for a transition period between unconsciousness and consciousness which is of great value in bridging this gap and makes it possible to combine during the same period the working through of material which was verbalized during the unconscious state.