This article employs population survey data for Trinidad and Tobago to investigate the likelihood of being married, both legal and common law in the present or the past, as compared to being never married, in a developing economy. The article finds support for the sex-specialized theory of marital formation, with men valued more and women valued less for their economic contributions to the family. Socioeconomic status and ethnicity play an important role in marital formation with sex specialization less likely to occur among Africans than the more advantaged ethnic groups. One of the consistent findings is that family structure matters crucially in predicting both legal and common law marriages. For example, living in a large, multigenerational household tends to impact the likelihood of marriage, as compared to remaining single, in opposite ways for men and women, with men in large households more likely to be married but women less likely to be married.