Dr. Horwitz completed a Ph.D. in clinical psychology in 1997 at the California School of Professional Psychology. Prior to graduate school he spent several years training at McLean Hospital in Boston, MA on the Adolescent and Family Treatment Unit with Edward Shaprio, MD the current director of Austin Riggs Institute.

While a graduate student at CSPP Berkeley, he trained in neuropsychology and also at the California Pacific Medical Center. While completing his dissertation, Dr. Horwitz worked as a research assistant for the Langley Porter Institute, and as a Care Manager for United Healthcare, both based in San Francisco, CA.

Shortly after earning the doctoral degree, Dr. Horwitz relocated to the East Coast and spent three years in a full time psychology residency at Chestnut Lodge Hospital in Rockville, MD where he co-managed their inpatient adolescent unit and performed a wide range of duties as a consulting psychology resident A major portion of his work involved adult psychotherapy, adolecsent psychotherapy, as well as psycho-diagnostic and psycho-educational assessment with children and adolescents. He worked closely with the medical staff and on-grounds special education school to integrate assessment data with diagnostic differentials, treatment planning, medication issues, and educational matters.

Immediately after the CL residency, Dr. Horwitz worked half time as a consulting psychologist in a special education private school conducting group and individual psychotherapy with learning disabled students. More recently, Dr. Horwitz has worked intensively in assessment with Sylvan Leaning Systems, the DC Public School District, a local assessment practice, and has just set up a private child assessment practice in N Berkeley, CA. His current interests are in psychoanalytic psychotherapy, pediatric psycho-educational and neuropsychological assessment, and personality assessment.