He developed the technique of "time-out" as a learning tool to shape behavior in children in the 1960s.
[1] He was a leader in creating the discipline of problem-solving, real-world psychological research known as applied behavior analysis.
He created the Teaching Family Model as an intervention program for dealing with juvenile delinquents.
[2] In the field of applied behavior analysis he introduced and named the concept of social validity.
[3] Donald Baer, Sidney W. Bijou, Todd Risley, James Sherman, and Wolf established the Journal of Applied Behavior Analysis, in 1968 as a peer-reviewed journal publishing research about experimental analysis of behavior and its practical applications.