In terms of program aesthetics, Z Cars attempted to counter the film appeal of early U.S. cop programs, such as Highway Patrol, with "gritty" realism. This was achieved by close attention to authentic police procedure, observation of working-class behavior, and, most especially, the adoption of regional speech. "Northern" working-class subject matter was prominent in 1960s culture, exemplified in feature films like Saturday Night and Sunday Morning and A Taste of Honey. However, Z Cars had more in common with the dialogue-led drama and actor-centered performances of ATV's Armchair Theatre and the early years of Granada's Coronation Street. Although later series were able to make more use of film and locations, the look of Z Cars was constructed almost entirely in the television studio. The 50 minutes of continuous recorded performance provided the space for displays of male comradeship and teamwork, sharp verbal exchanges with members of the community, and, most characteristic of all, intense drama in the interrogation room as Barlow bullied and coaxed confessions from his suspects.

     Overall, Z Cars succeeded in presenting a more human and down-to-earth image of the police than had been previously created on British television. Major crime remained at the periphery of the series, and the emphasis was placed instead on domestic and juvenile crime. The program adopted the social-democratic view of society so prevalent in 1960s Britain, and at times the police constables (PCs) behaved more like social workers than policemen, as criminal behavior was explained in terms of social deprivation. The liberal approach, however, was showing signs of exhaustion. Barlow upheld the law with a fierce authoritarianism in the station, and the PCs needed all their ingenuity and skill to enforce it effectively in the community. An ongoing theme was the personal cost of securing law and order, and most of the police characters had unsatisfactory family relationships. In one episode, for instance, Watt was shown agreeing to a divorce, and in another Steele beat up his wife. The image of police­ men as fallible human beings created some controversy, and for a time the chief inspector of Lancashire withdrew his support from the program, apprehensive that it might undermine public confidence in the police.

     In the course of its long run, the program established the reputations of many production participants, including actors such as Stratford Johns, Frank Windsor, Colin Welland, Brian Blessed, and James Ellis; producers and directors such as Shaun Sutton, David Rose, and John McGrath; and writers such as Troy Kennedy-Martin, John Hopkins, Alan Plater, and Allan Prior. Z Cars has been a major influence on the course of TV police fiction in Britain. The long-running CID (Criminal Investigation Department) series Softly Softly (1966-75) was a direct spin-off from  it, achieved by promoting Barlow to the rank of chief inspector, transferring him to a regional crime squad, and replacing the squad car with a dog-handling unit. More recent British programs about community policing as different as The Bill and Heartbeat have continued to draw from the Z Cars idea. One of the most interesting reworkings of the program's basic format was the BBC's Juliet Bravo (1980-88), which, in keeping with 1980s gender politics, transferred the power from male CID officers to a uniformed female inspector.