A Longitudinal Study of Vocational Commitment among Undergraduate Music Majors

John Holland (1985) proposed a vocational theory that organizes people into six vocational personalities (realistic, investigative, artistic, social, enterprising, and conventional) and organizes work environments into six corresponding categories. Holland claims that people search for occupations that are compatible with their vocational personality and avoid occupations that are incompatible. Behavior is assumed to be the result of the interaction between the vocational personality and the work environment. Previously, Holland, Whitney, Cole, and Richards (1969) had proposed a hexagonal model that describes the relationships among the six personality types. Degrees of similarity are indicated by the relative distances between the vertices of a hexagon. Theoretically, personality types and work environments that are adjacent on the hexagon share the greatest number of similarities, while opposing categories share few similarities. Categories that are neither adjacent nor opposite represent an intermediate degree of similarity. Holland’s theory also incorporates four constructs (congruence, consistency, differentiation, and identity) that attempt to explain sources of variability in occupational behavior. Congruence refers to the degree of compatibility between a person’s vocational personality