Marston was a lawyer and a psychologist; he also contributed to the first polygraph test, authored self-help books and created the character Wonder Woman. His major contribution to psychology came when he generated the DISC characteristics of emotions and behavior of normal people. Marston, after conducting research on human emotions, published his findings in his 1928 book called Emotions of Normal People in which he explained that people illustrate their emotions using four behavior types: Dominance, Inducement, Submission, and Compliance. He argued that these behavioral types came from people's sense of self and their interaction with the environment. He based the four types on two underlying dimensions that influenced people's emotional behavior. The first dimension is whether a person views his environment as favorable or unfavorable. The second dimension is whether a person perceives himself as having control or lack of control over his environment. Although Marston contributed to the theory of the DISC assessment, he did not create it. In 1956, Walter Clarke, an industrial psychologist, constructed an assessment which confirmed Marston's theory of the DISC model. Clarke created the Activity Vector Analysis, a checklist of adjectives on which he asked people to indicate descriptions that were accurate about themselves. This assessment was intended for use in businesses needing assistance in choosing qualified employees. Merenda, Peter F. and Clarke published their findings on a new instrument in the January 1965 issue of the Journal of Clinical Psychology." Instead of using a checklist, the "Self Discription" test forced respondents to make a choice between two or more terms. Factor analysis of this assessment added to the support of a DISC-based instrument. "Self Discription" was used by John Geier to create the Personal Profile System in the 1970s. Geier's DiSC assessment would eventually become Everything DiSC which is now owned by John Wiley & Sons. DISC has been used to help determine a course of action when dealing with problems as a leadership team—that is, taking the various aspects of each type into account when solving problems or assigning jobs.
