This chapter reflects on marriage from a legal perspective because it is more than a social, moral, religious or financial institution. It examines cross-national variations in the changes to the institution of marriage. The chapter focuses on the legal state of marriage, cohabitation and divorce by examining relevant legislation and changes that encourage different policy responses and how they are linked to relationship values—commitment, stability and responsibility. Marriage as a legal relationship stems from British practices. English marriage law enacted in 1753 became the basis for most of the US states' marriage laws. There was nothing in the descriptions of cohabitation or in its legal treatment to mislead couples into the belief. The British first administered marriage rulings in Australia which inherited British common law traditions. Those supporting same-sex marriage wish to share in marriage's values and traditions. Same-sex marriage persists on the parliamentary and political agenda.