Referring agents may ask independent medical evaluators if the examinee can return to work in either a normal or a restricted capacity; similarly, employers may ask external parties to conduct this type of assessment before a hire or after an injury. Functional capacity evaluations (FCEs) are used to measure agility and strength, but they have limitations and use technical jargon or concepts that can be confusing. This article clarifies key terms and concepts related to FCEs. The basic approach to a job analysis is to collect information about the job using a variety of methods, analyze the data, and summarize the data to determine specific factors required for the job. No single, optimal job analysis or validation method is applicable to every work situation or company, but the Equal Employment Opportunity Commission offers technical standards for each type of validity study. FCEs are a systematic method of measuring an individual's ability to perform various activities, and results are matched to descriptions of specific work-related tasks. Results of physical abilities/agilities tests are reported as “matching” or “not matching” job demands or “pass” or “fail” meeting job criteria. Individuals who fail an employment physical agility test often challenge the results on the basis that the test was poorly conducted, that the test protocol was not reflective of the job, or that levels for successful completion were inappropriate.