The changing climate of thought about children who break the law has shifted the emphasis in police work from the offense to offender, his needs, and his social background. A significant feature of police work with juveniles in recent years has been the strong drive in favor of the development of the policy of community involvement and juvenile crime prevention. Police frequently exercise discretion in issuing formal or informal warnings against repetition of antisocial conduct instead of reporting the available evidence to the appropriate prosecutor for consideration of proceedings. An informal, verbal warning may be issued by any officer on the beat who finds a child loitering in undesirable places with questionable company at night or playing truant from school. A recently instituted contact card system has made it possible to follow up such reports with a visit to the child's home, although the high volume of warnings has made followups difficult. Formal police warnings are conducted in the presence and with the consent of the parents by an officer in the rank of inspector or above. The child is warned of the consequences of his antisocial behavior, but only if he has admitted his guilt. Such warnings are a preventive measure aimed primarily at first offenders. The warning is formally recorded by the police, who use their discretion to the reporter. A second police system for dealing with juvenile offenders is the juvenile liaison. This followup procedure consists of a selected police officer maintaining contact with the offender and his parents and providing counsel whenever necessary in cooperation with social workers. In an attempt to improve police-community relations, uniformed beat officers undertake their normal police duties in addition to setting up community associations and youth clubs. The beat officer remains the most important individual in the whole of the police function, and cooperation between police and public, especially at the individual officer level, has proved to be the soundest means by which crime can be countered.