The problems of the number of core dimensions needed to describe a job, and the ability of the Job Diagnostic Survey to accurately measure these dimensions, were the basis of this study. The data was obtained by administering the Job Diagnostic Survey to 154 supervisors from eleven firms. This data was compared with United States data and showed that New Zealand supervisors scored generally higher on the test variables than did their United States counterparts. The profile of test scores closely matched that of the United States results, on which basis, it was concluded that the Job Diagnostic Survey could be used in the New Zealand situation for diagnostic and evaluative purposes. Further analyses were done, the first being a factor analysis which showed the Job Diagnostic Survey to be well constructed except for the core dimension variables which were shown to be three in number rather than five. A second analysis was done to assess the ability of the test to discriminate between groups, a task at which it proved to be reasonably effective. Because of an unexpected effect, thought to be attributable to one firm, a re-analysis of the data was performed, omitting the problem firm. The results of this re-analysis proved that the firm was having some effect, but that the effect was a complex one. The conclusions reached were that the Job Diagnostic Survey proved to be a reasonably constructed instrument albeit with some imperfections. The number of core dimensions was found to be three rather than five, although the imperfections in the test design was felt to be a contributing factor.