Vocational psychology, the psychological study of calling or ''life work'' (which for many is their work life), grew out of the vocational guidance movement. From the beginning, vocational guidance was founded on the Parsons formula of person analysis, job (or occupation) analysis, and the matching of the two. Vocational psychology, as a special case of the psychology of individual differences, has provided vocational guidance with an empirically validated technology (and accompanying theory) with which to assess the vocationally significant attributes of persons (abilities and interests, in particular), to describe occupations in person-attribute terms, and thereby to enable the matching of person and occupation on an actuarial basis. This technology has been amply validated for the prediction of both worker satisfaction and worker satisfactoriness. With the dramatic consequences for individuals and society of even modest increases in worker satisfaction and satisfactoriness, it is regrettable that vocational psychology is still unknown or unavailable to most of those who could benefit from it.