Anger arises when a person feels that he/she cannot control people, places, things, & events.
Anger comes from the need to be loved & recognized. When a person is fully realized (loved, recognized, appreciated, & fully comfortable with oneself) anger will subside & then cease.
The therapeutic procedure needs to include the client discovery process of where love was not provided &/or removed from the client's life. For this to work, the client must be taken back to the origin of events & helped to relive them so the loss can be experienced.