Career Choice and Development

Holland, 1972), and Bolles (1998) introduced the theory to the lay
public. Throughout this period, Holland was director of the Center for
Social Organization of Schools at Johns Hopkins University. During
this same period, the work on the classification of higher education
environments gave way to classification of work environments, and
intense attention turned to gender questions in interest measurement.
A significant advance in our understanding of the nature of inter-
ests was occasioned by the discovery of the structure that is revealed
in Holland’s hexagon (Holland, Whitney, Cole, & Richards, 1973;
see Figure 9.1), the full heuristic impact of which is only now being
appreciated (Rounds, 1995; Day & Rounds, 1998).
Two changes occurred during the 1980s. Gary Gottfredson initi-
ated a complex reanalysis of occupational description data that
resulted in the Dictionary of Holland Occupational Codes(Gottfredson
& Holland, 1996; Gottfredson, Holland, & Ogawa, 1982). This re-
analysis stimulated a revision of the Occupations Finder using job
activities. Whereas in the theory initially, environments were
defined by the number of individuals of a certain type inhabiting
that environment (for example, a social environment consisted of

HOLLAND’S THEORY 377

Note:R-person in an R-environment = 4; in a C- or an I-environment = 3; in
an E- or an A-environment = 2; and in an S-environment = 1.

Realistic Investigative

Enterprising

Conventional Artistic

Social

FIGURE9.1. The Holland Hexagon