The Supreme Court's recent decision in United States v. Windsor striking down a crucial section of the Defense of Marriage Act means that validly married same-sex couples are now entitled to the federal benefits associated with marriage. Subsequent decisions by various administrative agencies have construed entitlement to such benefits broadly, so that even couples whose marriage is not recognized in their state of residence can claim several important benefits, including the right to sponsor their spouses into the country for immigration purposes, and the right to file joint income tax returns. These rights, though, have not been extended to couples who are in civil unions. Even though civil unions were created as a way for same-sex couples to approximate marriage at the state level, it now appears that those in civil unions will not be able to gain the federal benefits of marriage. Thus, it is likely that states that currently recognize civil unions will soon switch to full marriage equality, and it is likely that no states will be added to the civil union roster. But the civil union has been transformed into something different in three states (Illinois, Colorado, and Hawaii), because the right to enter into these unions has been extended to opposite-sex couples, as well. Since those in opposite-sex relationships chose civil unions over marriage, it is likely that these states will continue to allow the civil union option for both opposite- and same-sex couples. This Essay explores what the continuing presence of civil unions in a few states is likely to mean in the ongoing national discussion about the structure and legal support for various types of families.