Studies designed to test the general hypothesis that individual differences in hypnotizability or suggestibility are related to differences among individuals in relatively enduring characteristics of personality are critically reviewed. A large number of studies using self-report inventories, projective tests, ratings, interviews, and other methods of personality assessment, failed to find reliable relationships between hypnotizability or suggestibility and traits of personality. A few investigators reported that hypnotizability or suggestibility is related to hysteria, neuroticism, extroversion, impunitiveness, tendency to repression, sociability, cooperativeness, and proneness to imaginative-fantasy experiences, but other investigators were unable to confirm these findings. The concluding section of the paper presents data to support the contention that individual differences in response to suggestions are more closely related to (1) differences among individuals in siruationally-variable characteristics such as relationship with E, attitudes toward the immediate test situation, and level of motivation with respect to performance on assigned tasks rather than to (2) differences among individuals in enduring and trans-situational characteristics of personality.