The relationship between the nine General Aptitude Test Battery (GATB) aptitudes as well as the GATB composite and success in a vocational-technical curriculum as measured by shop grades is investigated. Two different samples were used and both consisted of 10th grade boys enrolled in Shop Courses in the Altoona, Pennsylvania Area Vocational Technical School. Data was analyzed by computing zero order correlations and then submitting these to multiple regression analysis using the technique of elimination of variables by parsimony. The following results were found: (1) correlations were high enough to warrant development of aptitude patterns for individual shops, (2) certain aptitudes over a short period of training appear to be fairly stable, (3) variability exists from one sample to another and from one occasion to another in the degree of relationship between aptitudes and training success, (4) certain aptitudes are more improtant than others for success in vocational training, and (5) raw score grades may be as useful as converted grades as a criterion of training success. An implication from this study suggests grouping according to common aptitudes required as determined through empirical evidence rather than grouping shops together. (Author/EK)