The purpose of this research was to develop composites of subtests of the Armed Services Vocational Aptitude Battery (ASVAB) such that each composite score would be reliable and the various composite scores would be factorially independent of each other. Factor analysis was used to cluster the tests into composites based on the underlying dimensions of ability in the ASVAB. A principal factor solution was rotated to simple oblique structure to achieve the following five ability factors: (1) verbal; (2) analytic/quantitative; (3) clerical; (4) mechanical, including space perception; and (5) trade technical. These factors had high reliability and relatively low intercorrelations. One last score composite, called academic ability, was added to the factorially based composites as an indicator of the ability to succeed at further school or formal training. (Author/CTM)