Adoption is a process whereby a person assumes the parenting of another, usually a child, from that person's biological or legal parent or parents. Legal adoptions permanently transfer all rights and responsibilities, along with filiation, from the biological parents to the adoptive parents.
Unlike guardianship or other systems designed for the care of the young, adoption is intended to effect a permanent change in status and as such requires societal recognition, either through legal or religious sanction. Historically, some societies have enacted specific laws governing adoption, while others used less formal means (notably contracts that specified inheritance rights and parental responsibilities without an accompanying transfer of filiation). Modern systems of adoption, arising in the 20th century, tend to be governed by comprehensive statutes and regulations.