Issues such as stealth, uniformity, and safety seem obvious. In contrast, legal, philosophical, and fiscal concerns may be more subtle. Police agencies also need to consider the degree to which the patrol vehicle will actually be unmarked. Attractively marked police vehicles can be an important component of a community policing or service-oriented policing effort. Using unmarked cars can cause citizen concern. However, concealed or hidden tactics may be justified when on the lookout for a wanted person or in an area in which regular, visible patrols have been ineffective on controlling a particular traffic problem. Agencies that regularly use unmarked cars as part of traffic law enforcement should consider posting signs advising motorists that the police patrol with unmarked cars. The agency should also establish operating procedures that inform police officers how to identify themselves when making traffic stops and how to handle situations in which their identity is doubted. Address and telephone number from which to obtain more information or the report from which the information was taken