Interest scales designed to provide educational and vocational guidance to midshipmen at the U.S. Naval Academy were developed from the Strong Vocational Interest Blank. Three of the scales provided an index of similarity between a person's interests and the interests of previous graduates from each of the Academy's three academic areas: Engineering-Weapons, Mathematics-Science, and Humanities-Social Science. A fourth scale, the Applied-Science scale, was designed to distinguish the Engineering-Weapons majors from the Mathematics-Science students. These scales would also be used to satisfy the Navy's requirements for particular numbers of commissioned officers trained in each of the three broad areas. The four scales were cross-validated, and the validity of each scale was found to be significant. Four alternative strategies for utilizing the scales were discussed. When these strategies were compared with the probable scale results that would occur by chance, all four strategies were found to significantly improve upon the chance results. (Author/GDC)