foster care, generally, care of children on a full-time, temporary basis by persons other than their own parents. Also known as boarding-home care, foster care is intended to offer a supportive family environment to children whose natural parents cannot raise them because of the parents' physical or mental illness, the child's behavioral difficulties, or problems within the family environment, e.g., child abuse, alcoholism, extreme poverty, or crime. Such children are usually wards of the state. They may be placed by a state-approved agency in group homes, institutions (such as residential treatment centers), or with families who receive some payment toward care. The child's parents may retain their parental rights, and the child may ultimately return home. Under permanent foster care the agency has guardianship; the child may then be available for adoption by the foster parents or others. Foster care can also provide a supervised setting for adults with mental or emotional disabilities who cannot care adequately for themselves. The concept of foster care has been extended in recent years to include care for elderly persons, on a fee basis, in the homes of people who are not family members.