Above-level testing (also called "out-of-level testing," "off-grade testing," and "off-level testing") is the practice of administering a test level that was designed for and normed on an older population to a gifted child. This comprehensive literature review traces the practice of above-level testing from the earliest days of gifted education through the present. It was found that there were five reasons frequently given for above-level testing: raising the test ceiling, increasing score variability and discrimination, improving reliability, the sound interpretations of above-level test data, and reducing regression toward the mean. Although all of these reasons were theoretically supported, the strength of the empirical evidence varied. The article concludes by suggesting future directions of psychometric and applied research in above-level testing. (Contains 2 notes.)