While at the University of Chicago Porter was a peer of other notable American psychologists, including Carl Rogers, Thomas Gordon, Abraham Maslow and Will Schutz.
Porter's primary contributions to the field of psychology were in the areas of non-directive approaches, relationship awareness theory and psychometric tests.
In the mid-1930s, Porter was a student of Calvin S. Hall (who had just completed doctoral studies with Edward C. Tolman at University of California, Berkeley) and Robert W. Leeper (who was heavily influence by Kurt Lewin).
Following WWII, he returned to academia and his association with Carl Rogers by joining the faculty of the University of Chicago's Counseling Center.
The group designed training programs for counselors employed at the United States Veteran Administration, teaching them to use non-directive (client-centered) techniques.
I felt that problems considered on paper could do little to help counselors to recognize and deal with their basic attitudes…He has succeeded where to me failure seemed almost certain…It is hoped that it will have wide influence in stimulating constructive thinking about significant issues and problems in the growing field of psychotherapy.” Porter referenced the “in development” manuscript of Rogers’ landmark 1951 book Client-Centered Therapy and contributed to its development as evidenced by Rogers’ several references to Porter.
[6] Porter's involvement with the RAND Corporation yielded two noteworthy publications, an essay entitled "The Parable of the Spindle,"[7] and his 1964 book Manpower Development.
Porter's earliest known psychometric evaluations were performed with Rogers, and they measured the degree of directiveness or non-directiveness of a counselor using client-centered techniques.
[12] The theory itself is founded on four premises: Porter drew from Tolman's concept that “Behavior traits arise from purposive striving for gratification, mediated by concepts or hypotheses about how to obtain those gratifications.” [13] When combined with his research into Fromm's non-productive orientations and his frame of reference from University of Chicago peers Rogers and Maslow, Porter concluded that the primary motive all people share is a desire to feel worthwhile about themselves – and that each person is motivated to achieve feelings of self-worth in different ways.
Based on his observations with clients and ongoing research into the results of his own psychometrics, he stated, “When we are free to pursue our gratifications, we are more or less uniformly predictable, but in the face of continuing conflict or opposition we undergo changes in motivations that link into different bodies of beliefs and concepts that are, in turn, expressed in yet different behavior traits.”[15] Porter's description of the conflict sequence suggests that people experience changes in their motivation predictably and sequentially in up to three stages.