The Myers-Briggs Type Indicator is a Jungian-oriented self-report inventory which classifies people into dichotomous categories along four scales: extraversion-introversion, sensation-intuition, thinking-feeling, and judgment-perception. Introduced in 1942, the scoring and items have changed after several items analyses. Form F contains 51 phrase questions and 44 word pairs. A critical review of reliability and validity studies raises four issues to consider when evaluating the Indicator: (1) correspondence between Jung and Myers typology; (2) adherence to Myers' typology; (3) predictive validity; and (4) uniqueness. Myers has a different concept of the extroversion-introversion and judging-perceiving scales, but the scales do not reflect this concept. The Indicator generally does not reflect Myers' typology: classifications do not appear unchanging, interacting, or associated with different compounds of surface traits; in addition, type indeterminacy is unrelated to ineffective behavior and maladjustment. The Indicator may be useful for grade prediction in liberal arts schools, but its ability to identify vocational interest and creativity is limited. Finally, only the thinking-feeling scale is unique among existing scales; but factor analysis may uncover other unique properties. Norms are presented for high school, college, and graduate students; recently employed college graduates; and public school teachers. (CP)