Over the 4-year period, an estimated 258,460 incidents of firearm defense occurred, an annual mean of 64,615. Victims used firearms in 0.18 percent of all crimes recorded by the survey and in 0.83 percent of violent offenses. Considering violent crimes alone, an estimated 23,011,377 rapes, robberies, and assaults occurred over the 4-year period. Victims used firearms for self- defense in 190,483 of these crimes, an annual mean of 47,620. About 71 percent of defensive incidents involved crimes committed by strangers. Remaining incidents with known relationships were divided almost evenly between casual acquaintances and persons well-known to victims. Victims shot at offenders in 71,549 of these incidents, an annual mean of 17,887. In general, firearm self-defense was rare compared to gun crimes. Biases in National Crime Victimization Survey estimates are noted, and implications of the findings on victim use of firearms in self-defense are discussed. 26 references and 2 tables