Greenspoon made notable contributions to the field of behaviorism in psychology through pioneering work on verbal operant conditioning and counterconditioning in the treatment of anxiety.
[3] During his graduate school years at Indiana University he was directly supervised by Burrhus F. Skinner, William S. Verplanck, and J. R. Kantor.
He ran a private practice out of a mobile trailer during his time in Texas where he worked treating individuals, predominantly with anxiety disorders.
Greenspoon authored over 50 journal articles and book chapters and wrote two textbooks accumulating over 1600 citations in peer literature.
As an early proponent and central figure in the development of behavioral analysis in people, his work helped promote the field both in programming in universities across the nation and in scientific literature.
His selected works include: During his tenure at Arizona State University, Greenspoon supervised Robert O. Pihl’s graduate training.
Pihl went onto a highly successful career as a clinical psychologist spearheading the field of alcohol-related aggression and substance abuse research at McGill University.