In mobilizing the community to improve social service delivery, the aim is to enhance populations 'at risk' of engaging in criminal behavior so as to enhance their opportunities for mainstream success. This model assumes that communities have the tax base and the goodwill required to support such services and that the increased levels of intervention by therapeutic and correctional experts will be politically and socially tolerated. Moreover, even if social services are successful, coercion and repression are implicit in this model and its applications, since the persons targeted are expected to conform to the values and aims of the social control agencies. In the second model, the effectiveness of security systems within dwellings and businesses is the focus of crime prevention programs sponsored by police agencies. In most approaches used, police agencies define the nature of the problem, gather the information necessary to implement the measures, and also monitor program operations. This model tends to increase the involvement of police agencies in citizen affairs. Crime prevention through environmental design involves the application of the physical design principles of Oscar Newman to living areas so that they serve the interest of crime prevention. This latter model holds the greatest potential for citizen control of crime prevention efforts, although it is vulnerable to police and government control through ordinances affecting environmental design. Seventeen references are listed.