The historical development and recent applications are described of the picture sequencing format (PSF), a testing device which requires the subject to designate a complete and correct order for a set of related pictures. The earliest use was by Decroly in 1914 and perhaps the best known use is in the Wechsler intelligence tests. Special characteristics and qualities of the format are discussed. The author discusses four major areas within which the PSF may prove useful: (1) for the purpose of diagnostic or differential assessment; that is, broadly testing different areas of specific abilities in order to better grasp the pattern or profile of an individual's attainments; (2) for the testing of certain minority groups, for example the deaf and ethnic minorities; (3) as a predictive measure of certain practical, real life criteria, such as job success; and (4) as an intuitively appealing and entertaining measurement device useful in combatting low motivation, test anxiety, and negativism. (Author/CTM)