Psychiatric-mental health nursing promotes mental health through the assessment, diagnosis, and treatment of human responses to mental health problems and psychiatric disorders. A core mental health profession, it is a specialty that employs a purposeful use of self as its art along with a wide range of nursing, psychosocial, and neurobiological theories and research evidence as its science. Its areas of focus emerge based on current and anticipated societal needs, including disparities in mental health and its care and treatment among the diverse populations.