Professional caregivers work within the context of a center-based care (including crèches, daycare, preschools and schools) or a home-based care (nannies or family daycare). The majority of child care institutions that are available require that child care providers to have extensive training in first aid and be CPR certified. In addition, background checks, drug testing at all centers, and reference verification are normally a requirement. Child care can consist of advanced learning environments that include early childhood education or elementary education. "The objective of the program of daily activities should be to foster incremental developmental progress in a healthy and safe environment and should be flexible to capture the interests of the children and the individual abilities of the children." In many cases the appropriate child care provider is a teacher or person with educational background in child development, which requires a more focused training aside from the common core skills typical of a child caregiver.