This was a 2016 telephone-based survey of child care center directors randomly selected from a national database of licensed United States child care centers and queried about influenza vaccine requirements. Conceptually related items were grouped into 4 indexes: general infection control, use of health consultants, quality of child care, and pandemic influenza preparedness. These indexes, along with other center and director characteristics, were used to predict director-reported influenza vaccine requirements. Results. Of 518 child care center directors, only 24.5% and 13.1% reported an influenza vaccine requirement for children and adult caregivers, respectively. Center and director characteristics and the indexes were not associated with a director-reported influenza vaccine requirement. After adjusting for covariates, only having a state influenza vaccine law for children and an adult influenza vaccine requirement predicted having a child influenza vaccine requirement. Only having a child influenza vaccine requirement predicted having an adult vaccine requirement. (author abstract)