Arthur Janov was born in Los Angeles. Janov received his B.A. and M.S.W. in psychiatric social work from the University of California, Los Angeles and his Ph.D. in psychology from Claremont Graduate School in 1960. Janov originally practiced conventional psychotherapy in his native California. He did an internship at the Hacker Psychiatric Clinic in Beverly Hills, worked for the Veterans’ Administration at Brentwood Neuropsychiatric Hospital and has been in private practice since 1952. He was also on the staff of the Psychiatric Department at Los Angeles Children’s Hospital where he was involved in developing their psychosomatic unit.

Janov writes that his professional life changed in a single day in 1967 with the discovery of what he calls Primal Pain. During a therapy session, Janov heard what he describes as, “an eerie scream welling up from the depths of a young man lying on the floor”. He developed primal therapy, in which clients are encouraged to re-live and express what Janov considers repressed feelings.

Janov's patients included John Lennon and Yoko Ono.