TWO TABLES PROVIDE A DETAILED BREAKDOWN OF FINANCIAL AND HUMAN RESOURCES ALLOCATION IN THE FIELD OF PRIVATE BUSINESS SECURITY. ONE TABLE PRESENTS PUBLIC AND PRIVATE SECURITY EXPENDITURES AND EMPLOYMENT, AND THE OTHER PROVIDES SUMMARY DATA ON A RAND CORPORATION STUDY. EXTENSIVE FOOTNOTES ARE PROVIDED FOR BOTH TABLES. TOTAL PUBLIC AND PRIVATE SECURITY COSTS IN 1976 ARE ESTIMATED AT $20 BILLION AS COMPARED TO A 1969 COST OF NEARLY $9 BILLION. FULL-TIME PERSONNEL EXCEEDED 1 MILLION AS COMPARED TO 800,000 IN 1969. TOTAL NUMBER OF PERSONNEL (PART-TIME AND ADMINISTRATIVE/CLERICAL) CANNOT BE DETERMINED BECAUSE OF GAPS IN THE DATA. TOTAL 1976 COST OF SECURITY SERVICES AND EQUIPMENT IS ESTIMATED AT $5.9 BILLION. IN-HOUSE PERSONNEL PERFORM PRIMARILY GUARD AND DETECTIVE SERVICES. CONTRACT AGENCIES MAY PROVIDE ONE OR MORE OF THE FOLLOWING SERVICES: GUARDS, DETECTIVES, ALARM SERVICES, AND ARMORED CAR ESCORT. BETWEEN 1969 AND 1976 TOTAL EMPLOYMENT FOR PUBLIC AND PRIVATE SECURITY FORCES ROSE 3.8 PERCENT PER ANNUM AND TOTAL EXPENDITURES ROSE 12.2 PERCENT PER ANNUM. PRIVATE SECTOR GROWTH IN EMPLOYMENT AND EXPENDITURES WAS SLIGHTLY LOWER THAN FOR THE PUBLIC SECTOR. IN THE PRIVATE SECTOR, GROWTH IN CONTRACT SERVICES EXCEEDED GROWTH IN IN-HOUSE SERVICES. THERE WAS A SIGNIFICANT GROWTH IN THE NUMBER OF PRIVATE GUARDS AND WATCHMEN, BUT NOT IN THE NUMBER OF PRIVATE POLICE AND DETECTIVES. DIFFERENCES BETWEEN THE TWO MAJOR DATA SOURCES ARE BRIEFLY DISCUSSED. A BIBLIOGRAPHY OF SOURCES ADDRESSING ADDITIONAL ASPECTS OF SECURITY, PARTICULARLY PREVENTIVE SECURITY, IS ALSO PROVIDED. THESE ADDITIONAL SOURCES COVER SUCH TOPICS AS PERSONNEL TRAINING AND EVALUATION, SECURITY EQUIPMENT, PRIVATE SECURITY LICENSING AND REGULATIONS, RELATIONSHIPS BETWEEN THE PUBLIC AND PRIVATE SECURITY SECTORS, AND EFFECTS OF PROTECTIVE SECURITY COSTS ON PRODUCTIVITY.