The household and family structure in every major industrialized country changed in a fundamental way during the last couple of decades. First, marriage is less important today, as divorce, cohabitation, and single-motherhood are much more common. Second, female labor force participation has increased dramatically. As a result of these changes, today s households are very far from traditional breadwinner husband and housekeeper wife paradigm. These dramatic changes generated significant public interest and a large body of literature that tries to understand causes and consequences of these changes.This project has two main goals. First, it studies changes in household and family structure. The particular questions that it tries to answer are: 1) What are economic factors behind the rise in premarital sex and its destigmatization? What determines parents incentives to socialize their children and affect their attitudes? 2) What are the causes and consequences of the recent rise in assortative mating and diverging marriage patterns by different educational groups? 3) Why are marriage patterns among blacks so different than whites in the U.S.?The second aim of this project is to improve our understanding of income risk, the role of social insurance policies and labor market dynamics by building models that explicitly considers two-earner households. In particular, we ask the following set of questions: 1) What is the role of social insurance policies (income maintenance programs or progressive taxation) in an economy populated by two-earner households facing uninsurable idiosyncratic risk? 2) How does marriage and labor market dynamics interact and how important this interaction for our understanding of labor supply and marriage decisions?