The population of the St. John's metropolitan area grew by slightly more than 17 percent from 1971 to 1981, and from 1977 to 1981 the number of major crimes reported to police increased. Interview data revealed that the police had an especially clear conception of the downtown area, derived in part from its shift from a daytime business area to a night entertainment area, bringing an increase in policing problems during the evening. The police viewed other sections as having distinctive characters reflected in land use and housing types. Several elements contributed to the spacial imagery of the urban environment, including perceived landmarks, the channel of movement presented by the street network, and differences between commercial and residential land use. Factors which influenced police perceptions of a neighborhood were level of involvement in locally-based social relationships, class composition, and number of calls received from an area. Although St. John's is divided into 11 policing areas, echos of past divisions still influence officers' cognitive maps of the city. Drawing on their perceptions of trouble areas, officers see a direct correlation between row housing/public housing and crime. The police recognize the association between environmental design and criminality, citing shoplifting problems in shopping malls and school vandalism. Senior officers greatly influence new recruits' images of the urban environment, and the shared occupational identity tends to mute differences in imagery among officers. The paper discusses the impact of modernization in the police department and changes in the city on police views of the urban scene. Maps, diagrams, tables, and 28 references are supplied.