Hypnotic responses have been attributed to 2 mechanisms that are characterized as dissociative. In E. R. Hilgard's (1986) neodissociation theory, responses are hypothesized to be due to a division of consciousness into 2 or more simultaneous streams, separated by an amnesic barrier that prevents access to suggestion-related executive functions, monitoring functions, or both. In K. S. Bowers's (1992) dissociated control theory, hypnotic inductions are hypothesized to weaken frontal control of behavioral schemas, thereby allowing direct activation of behavior by the hypnotist's suggestions. The authors review the empirical base, conceptual issues, and strengths and weaknesses of both theories.