Where alcohol industry self-regulation is the primary protection against youth exposure to alcohol advertising, independent, systematic monitoring of youth exposure can promote public awareness of and greater accountability in the industry's practices. Using commercially available databases, the Center on Alcohol Marketing and Youth has combined occurrence and audience data to calculate youth (aged 12-20 years) and adult (above the United States legal drinking age of 21 years) exposure to alcohol advertising on television and radio, in magazines and on the Internet. This research in the United States shows that alcohol companies have placed significant amounts of advertising where youth are more likely per capita to be exposed to it than adults. Further analyses by the Center have demonstrated that much of this excess exposure of youth to alcohol advertising in the United States could be eliminated if alcohol companies would adopt a threshold of 15% (roughly the proportion of 12-20-years-old in the population 12 and above) as the maximum youth audience composition for their advertising. Although adoption of such a threshold would still leave much youth exposure to alcohol marketing in such "unmeasured" activities as sponsorships, on-premise promotions and campus marketing, it would assist alcohol companies in reaching their intended audiences more efficiently while reducing overall youth exposure to their advertising.