Adult foster care is typically arranged through governmental or private agencies, but it may be arranged by relatives who are unable to care for the adult in question. Adult foster care is often reserved for people who need assistance with daily tasks because of physical or mental disabilities. To explore this concept, consider the following adult foster care definition. Adult foster care commonly provides a supervised environment for adults that are unable to live independently due to a debilitating physical or mental condition. Adult foster care is typically reserved for people over the age of 18, but some homes accept residents as young as 16 years of age.