This report deals with the origin, development, verification, and revision of an occupational classification. John L. Holland ("The Psychology of Vocational Choice," 1966) proposed an a priori occupational classification of six categories: realistic, intellectual, artistic, social, enterprising, and conventional. These classes were defined in…

The author summarizes the origin of his occupational classification scheme, the main events in its development, and its present form. A number of deficiencies in this classification scheme are addressed, and the virtues of the scheme are enumerated. Although the present classification is the outcome of much empirical work, individual…

Self Directed Search (SDS) and Vocational Preference Inventory (VPI) results occupations and fields of study were organized to show the distributions of personalities within an occupation or field of study. The results show that single fields tolerate several types, but some types occur only infrequently. (Author)

The author reviews the evidence for the beneficial effects of the Self-Directed Search (SDS), indicates that Hanson and Prediger have misinterpreted the theory, that their evidence is misleading, and that other evidence indicates that males and females of the same type are similar. The virtues of raw scores are summarized. (Author)