Investigative strategies available to law enforcement efforts to combat underage drinking include: (1) Undercover Stings, during which a minor operative attempts to purchase alcohol from various licensed establishments such as convenience stores, restaurants, and bars; (2) Cops 'N Shops, in which an agent or officer poses as an employee or a customer in a retail establishment, waiting to arrest any minor attempting to purchase a alcohol, with a backup officer to apprehend individuals who legally purchase alcohol and give it to minors waiting outside; (3) Party Patrols, which call for undercover operatives to attend parties where they have been told underage drinking is to take place, or to observe the location and make arrests; and (4) Walk-throughs, a method for officers covertly, in plain clothes, or overtly, in uniform, to observe activity inside alcoholic beverage retail outlets. Certain legislative and policy actions may also effectively deter teenage alcohol use and reduce the number of alcohol-related crashes among young drivers: lowering legally acceptable levels of blood-alcohol content for drivers under 21; prohibiting driving by young, novice drivers during certain hours; and license suspensions for youths convicted of possessing alcohol or using a false driver's license to purchase alcohol. Notes