The 'new police' in England emerged as part of the reforms of the 1830's which centralized social policy. The police were formed to preserve the peace and protect persons and property. The place and potential of police leadership in the United Kingdom, Canada, and the United States rest on this early police mandate and its subsequent evolution in the social, ideological, and structural context of each country. In the United States, Jeffersonian and Jacksonian democracy emphasized local autonomy. In Canada, entrenched elite rule accentuated central control. British policing developed with a greater emphasis on autonomy than in Canada but less than in the United States. The growth of professionalized policing in the modern state, whether centralized or decentralized, has often failed to address effectively the challenges posed by pluralism, as uniform police practices are often insensitive to diversity in the populace. Order maintenance prior to the emergence of the modern state has some lessons for today. Among them is the value of community responsibility for social order and the legitimacy of diverse police services to reflect pluralism. 66-item bibliography. (Author summary modified)