The potential applications of occupational fitness assessment are briefly reviewed in the general context of recent human rights legislation. Limiting tasks in an industrial process must be examined, and bona fide occupational requirements must be defined in terms of psychomotor ability and physiological capacity. Heavy work may demand a high level of aerobic power, muscular strength, or tolerance of adverse environments. Such criteria can define an action limit, above which the task must be redesigned, or workers must be specially selected and trained. The courts may accept the results of field performance tests more readily than laboratory measurements of aerobic power or muscular strength. However, neither type of test currently has the reliability and validity needed to characterize the individual, or to distinguish a good worker from a poor worker. If the concern is public safety, employment must thus be based upon average data for a given population, while if the concern is employment equity, the only recourse seems a probationary period of employment.