Psychology is a broad academic, scientific and clinical discipline united by the fact that all psychologists engage in the study of mental (and often behavioral) processes. Here we limit discussion to the sub-field of Clinical Psychology – the application of psychological knowledge to the alleviation of human suffering.
Clinical Psychologists are usually doctoral level professionals having either a Ph.D. or Psy.D. degree requiring 5-6 years of study beyond completion of undergraduate college work, and a year long residency/internship at a clinic or hospital. The Ph.D. degree is generally granted to psychologists who have had scientific training (conducting research) in addition to training in providing therapy and assessment. The Psy.D. degree, in contrast, is granted to persons who have specialized more narrowly in becoming psychotherapists and clinical assessors.
Clinical Psychologists usually offer two skills to the healthcare marketplace. They are highly trained psychotherapists, and they are expert administrators and interpreters of psychological tests (IQ tests, personality tests, brain functioning tests, etc.). Psychologists are generally not able to prescribe medicine (exceptions to this generalization are found in the military, and in the states of New Mexico and Louisiana where properly trained psychologists have been granted the ability to prescribe psychoactive medications).