The results are based on field research and a synthesis of previous academic research on the subject. Part I examines the present European and French security problems which lead both private entrepreneurs and public agencies to seek the help of private security. Regardless of public police attitudes, private security has emerged as a major force in France's security. Part II presents a history of the evolution of private security and stresses that the requirements of insurance companies have been instrumental in shaping the means and methods of private security agencies. Part III shows the ruthless struggle for economic survival within the security industry; this struggle threatens the lawful and professional management of private police agencies because it makes their administrators too responsive to the demands of the market. Part IV shows the first successes of the French government in regulating private police by tracking the criminal records and salaries of its members. A full bibliography is appended.