The objective of this research, which was conducted with the cooperation of the U.S. Naval Academy, was the development of personality measures to supplement the more scholastically oriented aptitude tests used in the selection of Naval Officers. Approximately the first year of the research was devoted to an analysis of the ratings of aptitude-for-service, or leadership potential, used at the Naval Academy. The second phase of the research, which is described in the present report, involved the development and validation of several personality tests intended to predict midshipmen aptitude-for-service ratings. On the basis of findings obtained in the first phase of the research, five experimental personality tests were developed and administered in September 1951 to 462 midshipmen of the class of 1953. Three of these tests were objectively scorable: the Sense of Humor, Personality Trait, and Association Tests. Two of the tests, the Picture Interpretation and Story Completion Tests, were of the projective type. The first three tests showed virtually no correlation with the aptitude-for-service ratings. It is concluded that the objective tests included in the present analysis possess little or no validity for the prediction of aptitude ratings. The Story Completion Test yielded a small significant correlation (.25) with aptitude-for-service ratings. It is concluded that, with further refinements and research, including administration to pre-admission groups, this type of test may hold considerable promise for the prediction of aptitude-for-service ratings. It was not possible to analyze and validate the Picture Interpretation Test within the time and budgetary limitations of the present contract.