There is great variety among states regarding adoption laws, perhaps due to the very personal nature of these laws. As state governments began to take responsibility for regulating family relationships, they tended to develop very unique and regional variations on aspects of family law, including adoption. These variations spawned difficult legal conflicts as modern families grew more mobile, and these conflicts gave rise to the desire to standardize laws among the states into Model Acts and Uniform Laws. Although the need for adoption standardization is strong to date, only eight states have adopted the Uniform Adoption Act.

Any adult may adopt any other person with only minor logical restrictions. A married person must apply for adoption jointly with his or her spouse, for example, and, if the child in certain states is over the age of ten, twelve, or fourteen, the state will require his or her consent as well (except in Louisiana and Wisconsin, where the child's consent is not required). "Objective" standards, like Hawaii's requirement of a "proper" adopter, or Illinois's "reputable" one, and Virginia's "natural" one, also are present, as are specific requirements, for example, that the adopter be at least ten years older than the adoptee. Sometimes the adoptee must be a minor. In Florida homosexuals are, from the face of the statute, specifically excluded from adopting; it is unclear whether terms such as "proper," "reputable," or "natural" refer to a prospective parent's sexual orientation.

In general, family laws are changing as society's value system changes and is scrutinized. In the area of adoption, there is a growing trend to recognize the rights and opinions of children at younger ages, and to recognize the rights of non-traditional individuals. Indeed, same-sex couples are recognized as adoptive parents in a number of states. Also, some states appear headed in the direction of "open" adoption, whereby any individual may adopt any other individual for any reason.