The prescriptive authority for psychologists (RxP) movement is a movement in the United States of America among certain psychologists to give prescriptive authority to psychologists with predoctoral or postdoctoral graduate-level training in clinical psychopharmacology; successful passage of a standardized, national examination (Psychopharmacology Examination for Psychologists - Second Edition; PEP-2); supervised clinical experience; or a certificate from the Department of Defense Psychopharmacology Demonstration Project; or a diploma from the Prescribing Psychologists Register (FICPP or FICPPM) to enable them, according to state law, to prescribe psychotropic medications to treat mental disorders. This approach is non-traditional medical training focused on the specialized training to prescribe for mental health disorders by a psychologist. It includes rigorous didactics and supervised clinical experience. Legislation pertaining to prescriptive authority for psychologists has been introduced over 180 times in over half of the United States. It has passed in six states, due largely to substantial lobbying efforts by the American Psychological Association (APA), the largest professional organization of psychologists in the world with over 146,000 members. Prior to RxP legislation and in American states where it has not been passed, this role has been played by psychiatrists, who possess a medical degree and thus the authority to prescribe medication, but more frequently by primary care providers who can prescribe psychotropics, but lack extensive training in psychotropic drugs and in diagnosing and treating psychological disorders. According to the APA, the movement is a reaction to the growing public need for mental health services, particularly in under-resourced areas where patients have little or no access to psychiatrists. Currently, in states where RxP legislation has been passed, psychologists who seek prescriptive authority must possess a doctoral degree (PhD/PsyD), a license to practice independently, and completion of a Master of Science in clinical psychopharmacology (MSCP) degree or equivalent.