The Healthy Eating Index (HEI), a measure of overall dietary quality, allows researchers to assess, at a population level, compliance with the Dietary Guidelines for Americans (DGA) and the relationship between total diet quality and health outcomes. The 2015-2020 DGA 1 2015 Dietary Guidelines for Americans. https://health.gov/dietaryguidelines/2015/ Google Scholar are the current, prevention-focused nutrition and health policies of the United States. The DGA provide direction to policymakers and professionals as they design and implement nutrition-related programs and initiatives and conduct research to protect and improve the health and well-being of the American public. As Congressionally mandated directives, the DGA have major influence on the nation’s vast network of food programs, health care and nutrition services, and the research and educational activities overseen by the Department of Health and Human Services (DHHS) and the US Department of Agriculture (USDA). The DGA also have the potential to inform public health programming and professional practice at all levels where they influence the nutritional status and health of individuals, communities, and the entire population. Therefore, the DGA are an essential resource for nutrition and dietetics practitioners and others who seek to improve the nutrition-related well-being of individuals and communities they serve and attempt to reverse the prevalent diet-related problems of Americans. B. E. Millen is president, Millennium Prevention, Inc, Westwood, MA; chairman, Boston Nutrition, Inc, Westwood, MA.