The often confused fields of psychology and psychiatry, while related, are not the same. A psychiatrist is a medical doctor. As such, psychiatrists are qualified to not only perform mental evaluations of a patient, but they are also able to write prescriptions for medications, do physical exams, and have all the other capabilities of a family physician. A psychologist, on the other hand, may hold a doctorate in their field (a PhD.,) but they are not a medical doctor. Psychologists perform a range of activities related to mental health. Some specialize in patient evaluations, while others focus on research.

Those that focus on mental health evaluations usually specialize in a specific field of interest. Choosing social psychology leads to the study of interactions between individuals and groups. Psychologists that study counseling psychology work with clients that have problems ranging from mild to moderate mental disorders (such as depression or anxiety), to discontent at work, to difficulties in a relationship. Focusing on clinical psychology leads a psychologist to work with patients with more severe mental disorders, like schizophrenia or disorders of multiple personality.