THE FIRST PRIVATE SECURITY AGENCY, PINKERTON'S WATCHMAN SERVICE, WAS ESTABLISHED IN 1850 AS AMERICA BECAME MORE URBAN AND INDUSTRIAL; SMALL, ILL-EQUIPPED PUBLIC LAW ENFORCEMENT AGENCIES COULD NOT PROVIDE SUFFICIENT PROTECTION AGAINST CRIME. THE PRIMARY FUNCTION OF THE PINKERTON SERVICE WAS ASSETS PROTECTION. PRIVATE SECURITY GREW RAPIDLY DURING THE TWO WORLD WARS AND CONTINUED GROWTH WAS MOST EVIDENT DURING THE 1960'S. BY 1974, AGGREGATE ANNUAL EXPENDITURES FOR PRIVATE SECURITY WERE $6 BILLION; THE INDUSTRY EMPLOYED 1,000,000 PERSONS, COMPARED WITH THE 670,000 PERSONS EMPLOYED IN GOVERNMENTAL LAW ENFORCEMENT. THE SUCCESS OF PRIVATE SECURITY IS ATTRIBUTED TO THE SEVERE ECONOMIC IMPACT OF CRIME AND TO THE LIMITED RESOURCES OF PUBLIC AGENCIES, WHICH MUST BE RESPONSIVE TO LARGER PUBLIC NEEDS RATHER THAN TO PRIVATE INTERESTS. THE MAJOR COMPONENTS OF PRIVATE SECURITY ARE SECURITY GUARDS, INVESTIGATIVE SERVICES, ALARM SERVICES, AND ARMORED CAR SERVICES. PRIVATE SECURITY CAN BE EXPECTED TO CONTINUE ITS GROWTH PATTERN--MARKET ESTIMATES PREDICT A GROWTH OF 10 TO 12 PERCENT ANNUALLY--AND INCREASED RECOGNITION OF THE INDUSTRY AS AN INTEGRAL PART OF PUBLIC SAFETY AND CRIME PREVENTION IS PROBABLE. IT IS PREDICTED THAT THE ACADEMIC COMMUNITY WILL DEVELOP TRAINING PROGRAMS FOR PERSONS INTERESTED IN A PRIVATE SECURITY CAREER, THAT BUSINESS MANAGEMENT WILL UTILIZE PRIVATE SECURITY AND PREVENT CRIME-RELATED ECONOMIC LOSS, AND THAT INCREASED TERRORIST ACTIVITY IN THE 1980'S WILL MAKE PRIVATE SECURITY MORE IMPORTANT. PRIVATE SECURITY SERVICE DELIVERY WILL BE ENHANCED IN THE FUTURE BY TECHNOLOGICAL ADVANCES AND BETTER PERSONNEL TRAINING, AND GOVERNMENT WILL INCREASINGLY REGULATE THE INDUSTRY. IT IS ALSO PREDICTED THAT LOCAL LAW ENFORCEMENT WILL DEVELOP A CLOSER WORKING RELATIONSHIP WITH ALL COMPONENTS OF THE PRIVATE SECURITY INDUSTRY. REFERENCES AND TABULAR DATA ARE INCLUDED. (AUTHOR ABSTRACT MODIFIED--DAG)