As part of its 2011 commitment to the Partnership for Healthier America, the YMCA of the USA (Y-USA) pledged that by 2015, 85 percent of its local Y associations with early childhood or afterschool programs would have at least one program site that met 100 percent of the Y-USA's healthy eating and physical activity (HEPA) standards. To inform the measurement and monitoring of HEPA standards, the Y-USA designed a thirty-three-item online survey to assess which HEPA standards were being met in afterschool program sites each year in order to track progress over time. Verification activities including direct observation, key informant interviews, and document review generated overall compliance ratings for each standard. Compliance ratings were then compared to the self-reported survey results to determine the validity of the survey for assessing each HEPA standard. The survey had variable accuracy when compared to the validation methods. This chapter aims to inform the measurement and monitoring of HEPA standards implementation in larger afterschool networks by reporting on learnings from the Y-USA's early efforts in its network.