The U.S. Civil Service Commission conducted three criterionrelated validity studies for its PACE Test. The occupations studied were Customs Inspector, Internal Revenue Officer, and Social Security Administration Claims Authorizer. The criterion instruments for each study included a specially designed supervisory rating form, job information test, and work sample. For each criterion, scores were obtained separately for the occupational duties. A computer-analyzed task inventory was the keystone of the validity study. Data provided by the task inventory served the following functions: (a) to determine the extent of homogeneity of the occupation, (b) to select subjects for inclusion in the research study if the occupation turned out to be heterogeneous, (c) to measure the importance of the tasks performed in the occupation in order to constuct valid criterion instruments, and (d) to weight duty performance scores obtained by the research participants according to time spent in order to arrive at an overall measure ofjob success for each criterion instrument. Task inventory data were used in a somewhat different manner to construct the various criterion measures. Summary duty descriptions consisting of the most time-consuming tasks comprised the supervisory rating and ranking scales. Job information test items were employed if they measured the most time-consuming duties. The linkage between specific duties and the work sample items was made after the fact, since the work sample measured integral units of work performance. Only one time-consuming duty could not be measured by the criterion tests for one of the three occupations. It was concluded that the research design fostered the demonstration of the high validity of the PACE test.