Leopold Bellak (1916–2000) was a psychologist, psychoanalyst, and psychiatrist who pioneered the Children's Apperception Test (CAT).
He also collaborated on the Thematic Apperception Test (TAT), on clinical psychological assessments, and pioneered the understanding of ADHD (Attention Deficit Hyperactivity Disorder) as being a genetic disorder.
He was born in Vienna, Austria and as a refugee moved to the United States in 1939.
His tests and books are used in universities, and by clinicians globally.
He received the APA Award for Distinguished Professional Contributions to Applied Research in 1979.