Intimate partner violence (IPV) is a major public health problem in the United States. Results from a 1995 national study indicated that 23 percent of the black couples, 11.5 percent of the white couples, and 17 percent of the Hispanic couples surveyed reported an incident of male-to-female partner violence in the 12 months preceding the survey. The rate of female-to-male partner violence was also high: 15 percent among white couples, 30 percent among black couples, and 21 percent among Hispanic couples. The higher prevalence of IPV among ethnic minorities, compared with whites, cannot be explained by any single factor, but seems to be related to risk factors associated with the individual, the type of relationship between partners, and factors in the environment. Alcohol plays an important part in IPV. The study found that 30 to 40 percent of the men and 27 to 34 percent of the women who perpetrated violence against their partners were drinking at the time of the event. Alcohol-related problems were associated with IPV among blacks and whites, but not among Hispanics. Alcohol's role in partner violence may be explained by people's expectations that alcohol will have a disinhibitory effect on behavior or by alcohol's direct physiological disinhibitory effect. It is also possible that people consciously use alcohol as an excuse for their violent behavior or that alcohol appears to be associated with violence because both heavier drinking and violence have common predictors, such as an impulsive personality.