Act of transferring parental rights and duties to someone other than the adopted person's biological parents. The practice is ancient and occurs in all cultures. Traditionally, its goal was to continue the male line for the purposes of inheritance and succession; most adoptees were male (and sometimes adult). Contemporary laws and practices aim to promote child welfare and the development of families. In the latter part of the 20th century, there was a relaxation of traditional restrictions on age differences between adoptive parents and children, on the parents' minimum income level, on the mother's employment outside the home, and on placements across religious and ethnic lines. Single-parent adoptions and adoptions by same-sex couples also became more acceptable. Beginning in the 1970s, a growing adoptees-rights movement in the United States called for the repeal of confidentiality laws in most states that prevented adoptees as adults from viewing their adoption records, including their original birth certificates.