In Colorado, unless the adult seeking to adopt a child is a stepparent or close relative (kinship adoption), a licensed child placement agency must be involved in the process. Either a private adoption agency or the Department of Human Services may perform the relinquishment counseling for the birth parents and the home study of the adoptive parents. All adoptive parents must obtain a criminal records check prior to the adoption.

Adoption of a child causes the child to become the legal child of the adoptive parents for all purposes, and results in the issuance of a new birth certificate for the child, listing the adoptive parent or parents as the birth parents. Colorado also recognizes adult adoptions. Adoption of an adult simply makes the child equivalent to an heir at law of the adoptive parent; it is an estate planning tool.