The US Congress passed the Longshore and Harbor Workers’ Compensation Act (LHWCA) in 1927 to provide coverage to longshore laborers working on navigable waters of the United States when no state workers’ compensation law applied. After amendments that extended and standardized the Act, the Longshore Compensation Act provides more than $670 million in monetary, medical, and vocational rehabilitation benefits to more than 72,000 individuals annually. Under the LHWCA, ratings are performed for “scheduled injuries” (ie, a scheduled member of the body), including upper extremity injuries (excluding the shoulder), lower extremity injuries, and hearing loss. Impairment ratings typically are expressed in terms of whole person permanent impairment, but under the LHWCA impairment is expressed in the smallest applicable body part (eg, an injury of two digits is expressed as a hand rating). Definitions of terms such as injury, disability, and impairment are similar in the LHWCA and the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). Claims examiners are advised to require any physician selected to evaluate permanent medical impairment to use the AMA Guides, where applicable, to be detailed in their assessment report, and to rate and report permanent impairment according to the AMA Guides. Boxes in the article present portions of the LHWCA that address compensation for disability and the basic elements required to evaluate anatomical impairment.