| 1903 | The first meeting of the New York Branch of the APA was held. Edward L. Thorndike chaired the meeting. This organization was the forerunner of the modern Eastern Psychological Association. |
| 1955 | Johann Karl Friedrich Gauss, one of the first to describe the ubiquity of the normal distribution, was featured on a West German postage stamp. |
| 1955 | The Wechsler Adult Intelligence Scale was published. |
| 1963 | Psychologists Interested in the Advancement of Psychotherapy (PIAP), an organization founded in 1960, became a section of APA Division 12 (Clinical Psychology). Eugene Gendlin was the president of PIAP at the time. In 1967 this interest group again became independent as Division 29 (Psychotherapy) of the APA. |
| 1977 | The Rosemead Graduate School of Psychology, of Rosemead, California, became the first independent professional school of psychology to be accredited by a regional accrediting association, the Western Association of Schools and Colleges. The school specializes in pastoral counseling. |