The relevant laws addressed were enacted through the 1993-94 legislative session. Background information on current law discusses major changes in Chapter 20, laws of 1981, and other major changes since Chapter 20. The law's handling of repeat drunk-driving offenders is also explained. Part II describes the basic elements of and penalties for the various violations that involve operating a vehicle while under the influence of an intoxicant, drugs, or both. It also explains violations that involve operating an all-terrain vehicle, boat, or snowmobile while under the influence of an intoxicant, drugs, or both. Part III discusses the implied consent law applicable to motor vehicles; however, similar implied consent laws are in the statutes relating to the operation of a boat, all-terrain vehicle, and snowmobile while intoxicated. Under current law, any person who drives or operates a motor vehicle on the public highways of Wisconsin is deemed to have given consent to one or more tests of breath, blood, or urine to determine the presence or quantity of alcohol in the body. Part IV discusses law provisions that involve administrative suspension of a license to drive if a chemical test shows a high level of alcohol in the body. If test results show a prohibited level of alcohol concentration, the officer on the scene must report the test results to the Department of Transportation (DOT) and take possession of the person's license and forward it to the DOT. The person's operating privilege is then administratively suspended for 6 months. Part V explains laws that prohibit the possession or transportation of intoxicants in motor vehicles by persons under the legal drinking age and the general prohibition of drinking or possession of intoxicants in motor vehicles. The concluding section of this report examines selected laws in other States and recent proposals that bear upon the operation of a motor vehicle while intoxicated. Appended supplementary information