Wisconsin statutes define four degrees of sexual assault and establish penalities for each. The magnitude of the crime is affected by factors such as the extent of injury to the victim, the force or threat of force used and the victim's age. Any child between the ages of 15 and 17 years or a person who is mentally ill or unconscious is presumed incapable of consent, but that presumption may be rebutted. The 1975 legislation imposes limitations on admissible evidence concerning a victim's reputation and prior sexual conduct. Under a revised sex crimes law, persons judged guilty of first, second, or third degree sexual assault are sentenced and paroled like other criminal offenders; those sentenced receive an initial evaluation and enter an individualized program of educational, work, and psychosocial activities. In 1979, there were 758 forcible rape offenses reported in Wisconsin, a 12-percent increase over 1978 figures, and a 150-percent increase over 1970 reports. However, the incidence rate of forcible rape in Wisconsin is much lower than the national average. Specific statistics are detailed. Revised criminal sanctions, treatment programs and services, and prevention programs are described. The 1979 Wisconsin statutes relating to sexual assault, tabular data on the incidence of forcible rape and sexual assault and a bibliography of nine references are appended.