William Richards

William A. Richards is a clinical psychologist whose research career spans the original era of LSD psychotherapy and the contemporary renaissance in psychedelic clinical science. In the late 1960s and early 1970s he published influential clinical reports on LSD-assisted psychotherapy for patients confronting terminal illness and on adjunctive use of dissociative agents in addiction treatment, collaborating with colleagues such as Stanislav Grof. In subsequent decades he has continued to shape the field through empirical and methodological work on the psychospiritual effects of classic psychedelics, including controlled investigations of psilocybin's effects on religious and spiritual attitudes and behaviour.

In the 2000s and 2010s Richards contributed to the codification of safety and ethical guidelines for human hallucinogen research and authored the book Sacred Knowledge, which synthesises decades of clinical observations about psychedelics and religious experience. More recently he has been involved in developing and evaluating therapist training programmes and clinical protocols for psilocybin-assisted therapy in mood disorders, helping to translate historical clinical practice into standards for modern, regulated clinical trials. His work emphasises rigorous clinical care, integration, and the assessment of lasting psychological and existential outcomes following psychedelic-assisted interventions.