The concepts associated with work disability are not identical to those associated with medical disability. In addition to a worker's medical condition, the resultant functional limitations, and loss of participation in society, the injured or ill worker must often navigate a complex administrative system that often seems adversarial. This process is made less adversarial with the willingness to participate of knowledgeable clinicians. This article informs the interested clinician in regard to the unique aspects of work disability, including the issues of work accommodations, restrictions, and fitness for duty; prolonged work disability; and other return-to-work considerations at maximum medical improvement.