The sample of cases was selected to represent nearly 10,000 murder defendants and more than 8,000 murder victims in 1988 in the 75 most populated U.S. counties. Study data showed that about 8 in 10 murder victims were killed by relatives or acquaintances; strangers killed 1 in 10 murder victims. Among those arrested for murder and prosecuted, 63 percent were convicted of murder. Among those convicted of murder, 95 percent received a sentence of incarceration or death; 74 percent were sentenced to a prison term, 18 percent to a life sentence, 2 percent to a death sentence, and 2 percent to probation. Circumstances involving illegal drugs accounted for 18 percent of defendants and 16 percent of victims. About 75 percent of murder defendants and 44 percent of murder victims had been arrested or convicted in the past. Handguns were the most frequent murder weapon; they were used against 55 percent of black victims, 44 percent of white victims, 54 percent of male victims, and 36 percent of female victims. Female murder victims were about four times more likely than male victims to have died from strangulation or from injuries caused by a personal object used as a weapon. A spouse, romantic partner, or lover murdered more than 3 in 10 of female victims but 1 in 10 of male victims. In all victim age categories, more than one- third of murderers were in their 20's. Gang members comprised 7 percent of defendants, and one-third of victims belonged to a gang. A detailed description of the study methodology is also provided, including 25 tables and 2 figures.