The aim of this systematic review was to survey methods to assess the functional capacity of the musculoskeletal system within the context of work, daily activities, and sport. The following key words and synonyms were used: functional physical assessment, healthy/disabled subjects, and instruments. After applying the inclusion criteria on 697 potential studies and a methodological quality appraisal, 34 studies were included. A level of reliability > 0.80 and of > 0.60 resp 0.75 and 0.90, dependent of type of validity, was considered high. Four questionnaires (the Oswestry Disability Index, the Pain Disability Index, the Roland-Morris Disability Questionnaire, and the Upper Extremity Functional Scale) have high levels on both validity and reliability. None of the functional tests had a high level of both reliability and validity. A combination of a questionnaire and a functional test would seem to be the best instrument to assess functional capacity of the musculoskeletal system, but need further examined.