Dr. Leiken is a Distinguished Clinical Professor, Department of Psychiatry at the David Geffen UCLA School of Medicine where he was given the Career Achievement Award in 2004. He is a supervising and training analyst at the New Center for Psychoanalysis in Los Angeles and was president and is presently an instructor at the Los Angeles Child Development Center.

Dr. Leiken completed his undergraduate work at the University of Michigan and obtained his medical degree at St. Louis University Medical School. He served his residency at the UCLA Neuropsychiatric Institute and was a staff psychiatrist at Camarillo State Hospital in Camarillo California and ran a foster home for disturbed children connected to the hospital before entering into private practice.