In 2006, the New York City Department of Health and Mental Hygiene, seeking to address the epidemic of childhood obesity, issued new regulations on beverages, physical activity, and screen time in group child care centers. An evaluation was conducted to identify characteristics of New York City child care centers that have implemented these regulations and to examine how varying degrees of implementation affected children's behaviors. This article discusses results of this evaluation and how findings can be useful for other public health agencies. Knowing the characteristics of centers that are more likely to comply can help other jurisdictions identify centers that may need additional support and training. Results indicated that compliance may improve when rules established by governing agencies, national standards, and local regulatory bodies are complementary or additive. Therefore, the establishment of clear standards for obesity prevention for child care providers can be a significant public health achievement. (author abstract)