Hajo Müller is a clinical psychologist, licensed behavioral therapist and lead therapist at OVID Clinic Berlin conducting ketamine-augmented psychotherapy. In addition, he trains psychotherapists as a lecturer and supervisor and teaches meditation in the Augmented Psychotherapy Training (APT) . He has 10 years of inpatient therapy experience in a private clinic, including five years leading the addiction department. He recently published an educational DVD on substance use disorders with a big publisher (BELTZ).

He received a certificate for mindfulness in psychotherapy (Prof. Marsha Linehan and Prof. Dr. Martin Bohus) and attended various congresses and further training, especially in the field of third wave behaviour therapy and psychedelic-assisted psychotherapy. He has gained experience with various meditation and yoga teachers and is a Zen student of KyuSei Kurt Österle in meditation and archery.