Over half of rapes, robberies, and assaults are committed by strangers, and a conservative analysis indicates that stranger homicides are approximately 22 percent of urban homicides. Limited evidence suggests stranger homicides are increasing. Theoretically, research is hampered by the lack of uniform definitions of 'violence' and 'stranger.' Whether strangers are conceptualized in terms of categorical relationships, relational distance, or spatial distance, the definition of stranger relationships must take account of stranger interaction in the broader noncriminal social context. Although the evidence is limited, apparently felonies involving strangers differ from stranger nonfelony homicides with respect to the location of the offense and the number of witnesses. It is also apparent that stranger homicides, both felony and nonfelony, have a substantial interracial component. Evidence suggests there may be two types of stranger relationships relevant to understanding violence. Regarding the responses of the criminal justice system, whether the offender and victim are strangers is one of the three major factors that affect virtually every major decision in criminal justice processing. 168 footnotes.