During much of the twentieth century, matching was the philosophy that governed non-relative adoption. Its goal was to make families socially that would “match” families made naturally. Matching required that adoptive parents be married heterosexual couples who looked, felt, and behaved as if they had, by themselves, conceived other people’s children. What this meant in practice was that physical resemblance, intellectual similarity, and racial and religious continuity between parents and children were preferred goals in adoptive families. Matching was the technique that could inject naturalness and realness into a family form stigmatized as artificial and less real than the “real thing.” Matching stood for safety and security. Difference spelled trouble.

Under the matching paradigm, one family was substituted for another so carefully, systematically, and completely that the old family was replaced, rendered invisible and unnecessary. This was not usually the case before the twentieth century. Children who were placed did not lose contact with their natal kin, even in the case of very young children placed permanently for adoption. The only matching required by early adoption laws was matching by religion, and these laws were frequently disregarded by child-savers, such as Charles Loring Brace, who preferred matching children with the (Protestant) religion of the placing organization, rather than that of (Catholic) natal kin. In the nineteenth century, many adoptions involved sharing children rather than giving them away.

In contrast, matching was an optimistic, arrogant, and historically novel objective that suggested that a social operation could and should approximate nature by copying it. Between 1920 and 1970, matching was popular, especially among infertile couples who sought to adopt because they were unable to conceive children of their “own.” By midcentury, infertility had become an unquestioned qualification for adoption. This reinforced the notion that matching compensated for reproductive failure by promising relationships that could pass for the exclusive, authentic, and permanent bonds of kinship that were only natural.

Matching confronted the central problem of modern adoption. It attempted to create kinship without blood in the face of an enduring equivalence between blood and belonging. The results were paradoxical. Matching reinforced the notion that blood was thicker than water, the very ideology that made adoption inferior, while seeking to equalize and dignify it.

The naturalness of matching still has ardent defenders today, especially with regard to race. Since 1970, however, its dominance has been criticized by movements opposing confidentiality and sealed records. Transracial adoptions and international adoptions also challenge matching by celebrating families deliberately and visibly formed across lines of race, ethnicity, and nation. Open adoption arrangements undercut matching too. They acknowledge an obvious truth that matching concealed: it is possible to have more than one mother, one father, one family.