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 five 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. Current programs that offer the MSCP degree are: The California School of Professional Psychology at Alliant International University, The Chicago School of Professional Psychology, Drake University Fairleigh Dickinson University, Idaho State University, and New Mexico State University. In some jurisdictions, completion of the training programs from the Department of Defense or the Prescribing Psychologists' Register Diplomate Certification also satisfies the licensing law requirements. The supervised clinical experience required after completing the MSCP and passing the PEP varies by jurisdiction, but typically requires a specific number of hours of supervised experience and/or a specific number of patients. Some jurisdictions then grant conditional prescribing psychology licenses or certifications, while others grant full prescribing authority after the supervised clinical experience has been successfully completed. The medications the psychologist may then prescribe are limited to those indicated for psychiatric problems; still, the specific medications that are able to be prescribed by prescribing or medical psychologists varies by jurisdiction.

Psychologists' involvement in pharmacotherapy exists on a continuum, with psychologists serving as prescribers, collaborators, and information-providers in the medical decision-making process. Currently, psychologists may prescribe in six states: New Mexico, Louisiana, Illinois, Iowa, Idaho, and Colorado, as well as in the Public Health Service, the Indian Health Service, the U.S. military, and the U.S. territory of Guam. When psychologists act as collaborators, they lack the authority to make the final decision to prescribe; however, they may assist in the process by recommending clinically desirable treatment effects, certain classes of medications, specific medications, dosages, or other aspects of the treatment regimen. Psychologists also provide information that may be relevant to the prescribing professional. Psychologists may express concerns about treatment, refer patients for medication consultations, direct patients to referral or information sources, or discuss with patients how to address their concerns about medication with the prescriber.