According to ACGME, addiction psychiatry focuses on the prevention, evaluation, and treatment of substance-related disorders as well as related education and research. The addiction psychiatrist is proficient in techniques required in the treatment of the larger group of patients with dual diagnoses of addictive disorders and other psychiatric disorders. 

According to ACGME, child and adolescent psychiatry is a medical specialty focused on the prevention, diagnosis, and treatment of disorders of thinking, feeling, and behavior affecting children, adolescents, and their families.

According to ACGME, consultation-liaison psychiatry is the discipline encompassing the study and practice of psychiatric disorders in patients with medical, surgical, obstetrical, and neurological conditions, particularly for patients with complex and/or chronic conditions. Physicians specializing in consultation-liaison psychiatry have expertise in the diagnosis and treatment of psychiatric disorders in complex medically ill patients. The practice of consultation-liaison psychiatry requires comprehensive knowledge of patients with acute or chronic medical, neurological, or surgical illness in which psychiatric morbidity affects their medical care and/or quality of life, patients with somatoform disorder or with psychological factors in which psychiatric morbidity affects a physical condition, and patients with a psychiatric disorder that is the direct consequence of a primary medical condition.

According to ACGME, forensic psychiatry focuses on interrelationships between psychiatry and the law (civil, criminal, and administrative), including the psychiatric evaluation of individuals involved with the legal system, or consultations on behalf of the third parties such as employers or insurance companies; the specialized psychiatric treatment required by those who have been incarcerated in jails, prisons, or special forensic psychiatric hospitals; active involvement in the area of legal regulation of general psychiatric practice; and, related education and research
efforts.

According to ACGME, geriatric psychiatry focuses on prevention, diagnosis, evaluation, and treatment of mental disorders, and signs and symptoms seen in older adult patients. An educational program in geriatric psychiatry must be organized to provide professional knowledge, skills, and opportunities to develop competency through a well-supervised clinical experience.

According to ACGME, sleep medicine is a discipline of medical practice in which sleep disorders are assessed using a combination of clinical evaluation and physiological monitoring, and treated using medications, medical devices, surgical procedures, patient education, and behavioral techniques. Sleep medicine fellowships provide advanced education to allow a fellow to acquire competency in the subspecialty with sufficient expertise to act as an independent consultant.