One hundred of 150 patients with non-psychotic functional psychiatric disorders were benefited by the use of LSD psychotherapy. The dosage of LSD employed was 25 to 2000 micrograms intramuscularly per session for from one to 10 sessions. On this regimen four patients became psychotic and required electroconvulsive therapy. None were permanently harmed.Indications for and contraindications to this form of treatment and a procedure involving a doctor and a nurse as co-therapists are discussed. In particular, LSD is considered to permit "perceptualization of the transference".LSD possibly extends the scope and value of the psychotherapeutic approach in such cases.