Impaired physicians are unable to manage professional activities safely. Impairment can be the result of physical or mental disorders, but impaired physicians commonly refers to those suffering from substance use disorders. These disorders are at least as common in physicians as they are in the general population, and physician health programs have been established in each state to provide expeditious and detailed evaluation, referral to treatment facilities, and post-treatment monitoring to ensure compliance. These programs protect participants against sanctions and safeguard patients. The prognosis for participants is excellent, with more than 70% able to practice medicine at 5 years.