Mothers Against Drunk Driving (MADD) has arguably been one of the most successful public-health grassroots citizen advocacy organizations in the United States in the past century. In 2005, MADD celebrated the 25th anniversary of its founding. Based on a national poll by the Gallup Organization in 2005, MADD is recognized by 94% of citizens. It is generally given credit for changing American attitudes toward drinking and driving. Since MADD's founding in 1980, alcohol-related traffic deaths in the United States have decreased from an estimated 30,000 to 16,694 in 2004, according to the National Highway Traffic Safety Administration. This article examines the growth of MADD since its founding and attempts to gauge its contribution to the public's understanding of the impaired-driving problem and to the reductions in alcohol-related highway deaths and injuries that have occurred in the first 25 years of its existence.