Background: Childhood obesity is a pressing public health concern; the prevalence of childhood obesity is 15.5% in Virginia. About 15% of Virginia's K-12 population participates in after-school programs (ASPs), identified as appropriate venues in which to promote healthy eating. In 2011, the National Afterschool Association (NAA) adopted the evidence-based Healthy Eating and Physical Activity Quality Standards (HEPAQS) to address snack quality and physical activity in ASPs. Although research has indicated promise in implementation of such policies in after-school programs, a need for assessment of effectiveness still exists. Are the quality standards being implemented effective in increasing positive nutritional habits among children in ASPs? In 2014, Danville Parks and Recreation (PandR), a key partner in the Dan River Partnership for a Healthy Community (DRPHC), adopted the HEPAQS policies to improve the nutrition and physical activity of attending students. Objective: The primary purpose of this study was to determine the effectiveness of the adopted HEPAQS Healthy Eating standards by comparing the quality of snacks served at the ASP sites before and after the HEPAQS policies were implemented. A secondary purpose of this study was to describe the quality of snacks among both policy-adoption and comparison sites. The tertiary purpose of this study was to compare the quality of program versus non-program snacks in the ASPs. Methods: To meet the objective, a natural experiment followed a pre-post evaluation design to determine the impact of adoption of the Healthy Eating standards at three policy-adoption ASPs. Applying an interrupted time series design, a total of 531 children's snack observations were performed across all sites during a five-week pre-policy adoption data collection period and 412 total snack observations were performed during a six-week post-policy data collection period. Direct observation methods including a modified quarter-waste method for dietary observations and the HAAND tool were conducted by trained research staff to collect snack quantity, type, brand, and amount consumed. Observational data was entered into statistical software for hypothesis testing. Data were also analyzed using Nutrition Data System for Research (NDSR) software to determine the mean servings, fluid ounces, or grams of each nutrient specified in the adopted Healthy Eating standards. Results: Adoption of the Healthy Eating standards among the three policy-adoption sites did not result in better snack quality based on adherence to the Healthy Eating standards. Policy-adoption sites were only meeting four of the nine adopted Healthy Eating standards post-policy, almost all of which were also being met pre-policy: serving foods without trans-fats, serving no sugar-sweetened beverages (SSBs), limiting fruit juice to one 8 oz. serving, and avoiding artificially sweetened beverages. By post-policy data collection, policy-adoption sites were not meeting five of the nine adopted standards: weekly serving a fruit or vegetable, offering water at all times, serving no candy or sugar-based snacks, emphasizing whole grains, and serving no snack chips. Although no significant changes were expected among comparison sites, they saw a significant increase in 100% fruit juice consumption and a decrease in grams of trans-fat from pre- to post-policy data collection. Across all five sites, program snacks were generally healthier than non-program snacks, as program snacks contained less SSBs, sweets, and snack chips. Conclusion: Adoption of the Healthy Eating standards among the three policy-adoption sites did not result in better snack quality. Pursuing additional HEPAQS regarding implementation, staff training, and social and program support may be necessary to impact snack quality. ASPs may improve non-program snack quality by addressing HEPAQS for vending machines and guidelines provided to parents regarding non-program snacks. The PandR partners of the Dan River Partnership for a Healthy Community should continue to seek support as they implement the Healthy Eating standards in their ASPs. / Master of Science