Now that the Supreme Court has reshaped the laws of marriage, attention is shifting to nonmarriage. The law no longer treats intimate couples who do not marry as either deviant or deprived. Yet, rather than regulate nonmarriage in a systematic way, the law applies two inconsistent doctrines to govern these relationships. This Article is the first to explore the fundamental contradiction in the legal approach to unmarried partners. While the laws governing financial obligations between unmarried couples are moving toward a deregulatory model that radically differs from the status-based regulation of marriage, the laws of custody and support insist on imposing normative obligations identical to those involved in marriage, whatever the actual arrangement between the parties. This Article provides a new theory for the current legal regulation of nonmarriage. This Article examines the different trajectories of the two bodies of law -- financial and custodial obligations -- that underlie the legal treatment of nonmarriage. It shows how the financial law of nonmarriage reflects women's growing economic independence and the deregulation of adult relationships. By contrast, custody and support law are rooted in an older view of parental obligations that is contrary to emerging community norms about unmarried parenting. Consequently, as this Article shows, the laws of marriage, which envision a single coherent institution, are an inappropriate model for the laws of nonmarriage. Finally, this Article articulates a framework to provide a coherent legal approach to nonmarriage. As marriage -- and nonmarriage -- become true choices, it will be increasingly important to address what full legal respect for these choices entails.