Specifically advocated is citizens' use of whistles as a crime prevention measure to alert neighbors of impending trouble, the presence of suspicious characters, unusual events, or confrontations of potential violence. The vignette illustrates a young woman's error in judgment at two critical moments. Upon being accosted by a stranger on the street near her home, she decides to try evading him without a call for help. Having reached safety, she decides not to report the incident to the police. The stranger appears again, approaching her with even greater violence, and this time she uses her whistle. Her signal is picked up by a watchful neighbor, the molester becomes frightened, and she is able to telephone the police. Everyone involved experiences relief when police officers apprehend and arrest the molester as a result of the responsible and cooperative actions of neighborhood residents.