In 1964, Kitty Genovese was murdered outside her home in New York City late at night. She fought back, and the murder took over half an hour. At least 38 neighbours heard her screams for help, but nobody came to her aid. No one even called the police. The American public was horrified by this incident, and social psychologists began to investigate the causes of what at first was termed “bystander apathy”. Their work showed that “apathy” was not a very accurate term, however. It is not simple indifference that prevents bystanders from intervening in emergencies. First, there are realistic deterrents such as physical danger. Second, getting involved may mean lengthy court appearances or other entanglements. Third, emergencies are unpredictable and require quick, unplanned action; few of us are prepared for such situations. Finally, one risks making a fool of oneself by misinterpreting a situation as an emergency when it is not. Researchers concluded that “the bystander to an emergency situation is in an unenviable position. It is perhaps surprising that anyone should intervene at all”.