The Graduate Record Examinations (GRE) Aptitude and Advanced Tests were evaluated as predictors of a dichotomous criterion of whether or not the candidate attained the doctorate within a specified length of time. More specifically, the project attempted to define subgroups for which the GRE tests have varying degrees of validity, and to provide biographical profiles of each subgroup as well as the optimal predictive equation for those subgroups. The GRE-Advanced tests were consistently found to be the best predictors of Ph.D. attainment. However, the predictive accuracy of the GRE-Advanced test varied considerably across graduate fields and in one case within a graduate field. That is, prediction on the whole was considerably more accurate in the "hard science" graduate areas of mathematics and chemistry than in psychology. Within the psychology area, there was a "u" shaped relationship between predictability and age. That is, the total sample regression equation led to greater predictive accuracy for the younger and the older age groups. The middle age group (25-26 years old) was not only less predictable, but the errors in prediction tended to lead to underestimation of their actual rate of Ph.D. attainment. (Author/ROF)