Rudolf Dreikurs (1897-1972) was an Austrian-American psychiatrist and psychologist, and a prominent figure in Adlerian psychology. As a student and colleague of Alfred Adler, he played a crucial role in developing and spreading individual psychology in the United States. Dreikurs is best known for his work in child psychology and family counseling, particularly his concept of "logical consequences" in child discipline. His influential book "Children: The Challenge" became a classic in parenting literature.