This report investigates the appropriateness of using the General Technical (GT) composite of the Armed Services Vocational Aptitude Battery (ASVAB) as a reenlistment criterion. Three aptitude measures, all ASVAB composites, were compared to measures of proficiency in job performance: the Armed Forces Qualification Test (AFQT), the GT, and the specific Aptitude Area (AA) composites. The GT is similar to the AFQT except for exclusion of a speed test. The AA composites are differential aptitude measures and would be expected to provide a better prediction of performance in specific military occupational specialities (MOS). The predictive ability of each of these composites was analyzed and the results compared. Job proficiency was measured by the Skill Qualification Test (SQT). The univariate and multivariate statistical methods used in this research demonstrated that all aptitude measures were significantly related to performance across MOS and skill levels. This is true even when variables measuring experience and education are included in the analysis. The specific AA composites generally predicted performance better than AFQT or GT. The results suggest that, when no MOS-specific performance measures are available, AA scores are the preferable reenlistment criteria relative to either AFQT or GT scores. (Author/PN)