A theory is, in effect, a rationalized set of assumptions or hypotheses that allows you to explain the past and predict the future. These ideas are still part of our career counseling approach today. This typology theory was developed to organize the voluminous data about people in different jobs and the data about different work environments, to suggest how people make career choices and to explain how job satisfaction and vocational achievement occur. Holland based his theory of personality types on several assumptions.
People tend to choose a career that is reflective of their of their personality.
Because people tend to be attracted to certain jobs, the environment then reflects this personality. He suggests that the closer the match of personality to job, the greater the satisfaction. All types are part of each of us. However, one type is usually evidenced most strongly. We may even resemble up to three of the types.