Psychiatrist
A psychiatrist is a physician who specializes in psychiatry and is certified in treating mental illness.  As part of their evaluation of the patient, psychiatrists are one of only a few mental health professionals who may prescribe psychiatric medication, conduct physical examinations, order and interpret laboratory tests and electroencephalograms, and may order brain imaging studies such as computed tomography or computed axial tomography, magnetic resonance imaging, and positron emission tomography scanning.

# Psychiatry in the professional world
Psychiatrists are doctors of medicine or osteopathy and are certified in treating mental illness using the biomedical approach to mental disorders.  Psychiatrists may also go through significant training to conduct psychotherapy, psychoanalysis, and/or cognitive behavioral therapy, but it is their medical training that differentiates them from other mental health professionals.

## Subspecialties
The field of psychiatry itself can be divided into various subspecialties. These include:
- Child and adolescent psychiatry
- Adult psychiatry
- Psychiatry of Old Age (Geropsychiatry)
- Learning disability
- Behavioral medicine
- Consultation-liaison psychiatry
- Emergency psychiatry
- Addiction psychiatry
- Forensic psychiatry
- Combined Internal Medicine and Psychiatry (Med-Psych)
- Combined Family Medicine and Psychiatry
- Combined Neurology and Psychiatry
- Combined Pediatrics, Psychiatry and Child Psychiatry
Some psychiatric practitioners specialize in helping certain age groups; child and adolescent psychiatrists work with children and teenagers in addressing psychological problems. Those who work with the elderly are called geriatric psychiatrists or geropsychiatrists. Those who practice psychiatry in the workplace are called industrial psychiatrists in the US (occupational psychology is the name used for the most similar discipline in the UK). Psychiatrists working in the courtroom and reporting to the judge and jury, in both criminal and civil court cases, are called forensic psychiatrists, who also treat mentally disordered offenders and other patients whose condition is such that they have to be treated in secure units.
Other psychiatrists and mental health professionals in the field of psychiatry may also specialize in psychopharmacology, neuropsychiatry, eating disorders, psychosomatics, and early psychosis intervention.

# Professional requirements
Typically the requirements to become a psychiatrist are substantial but differ from country to country.
In the United Kingdom, the Republic of Ireland, and other parts of the world, one must pursue a Bachelor of Medicine and Surgery, or a "first MB." These degrees are often abbreviated MB BChir, MB BCh, MB ChB, BM BS, or MB BS.  Following this, the individual will act as a "foundation programme trainee" for two additional years.  The foundation programme allows students to experience the different specialties of medicine, as well as learn important attributes and qualities of becoming a doctor.  Upon completion, a student can apply for training to specialize in psychiatry.  Following acceptance, this specialized training will last for about 6 years.  After training is successfully completed, the individual can apply for a consultant post and start a career as a licensed psychiatrist.
In the United States and Canada one must first complete their Bachelor's degree.  Students may typically decide any major of their choice, however they must enroll in specific courses, usually outlined in a pre-medical program.  One must then apply to and attend 4 years of medical school in order to earn their MD or DO and to complete their medical education.  Following this, the individual must practice as a psychiatric resident for another four years (five years in Canada). Psychiatry residents are often required to complete at least four post-graduate months of internal medicine or pediatrics and two months of neurology during the first year. After completing their training, psychiatrists take written and then oral board examinations.  The total amount of time required to complete post-baccalaureate work in the field of psychiatry in the United States is typically 8 to 9 years.