UNDER EXECUTIVE ORDER NO. 10450 AND OTHER PUBLIC LAWS, THE AGENCIES MAKING PERSONNEL SECURITY INVESTIGATIONS ARE THE OFFICE OF PERSONNEL MANAGEMENT (OPM), THE DEFENSE INVESTIGATIVE SERVICE, THE FBI, THE DEPARTMENT OF STATE, SEVERAL UNITS OF THE TREASURY DEPARTMENT, AND A FEW OTHER AGENCIES. COSTS FOR INVESTIGATIONS IN DIFFERENT AGENCIES VARY WIDELY AND CANNOT BE COMPARED BECAUSE NO UNIFORM METHOD EXISTS FOR DEVELOPING THE COSTS OF INVESTIGATIONS. SAVINGS FROM TRANSFERRING INVESTIGATIVE ACTIVITIES TO A SINGLE AGENCY WOULD BE LIMITED TO SUCH BENEFITS AS THE ELIMINATION OF DUPLICATE OR UNNECESSARY OVERHEAD AND THE STABILIZATION OF THE WORKLOAD. COSTS MAY INCREASE AS A RESULT OF CONSOLIDATION, HOWEVER, BECAUSE SOME AGENCIES HAVE INDICATED A DESIRE TO RETAIN INVESTIGATORS FOR OTHER WORK. THE OPM SHOULD WORK WITH OTHER AGENCIES TO DEVELOP DEFINITIVE STANDARDS FOR REPORTING COSTS AND DETERMINING THE SCOPE OF INVESTIGATION. AGENCIES SHOULD AGREE TO USE SUCH STANDARDS, SHARE RESOURCES WHEN APPROPRIATE, AND USE IMPROVEMENTS MADE BY OTHER AGENCIES. THE OPM SHOULD IMPROVE ITS OWN INVESTIGATIVE PROGRAM REGARDING CONTROLS OVER WRITTEN INQUIRIES AND THE DEVELOPMENT OF ADEQUATE CLASSIFICATION CRITERIA. THE APPENDIXES CONTAIN CONTACTS PER CASE, A LETTER, AND A DESCRIPTION OF INVESTIGATIONS. (AUTHOR ABSTRACT MODIFIED--RCB)