Thesis advisor: Peter GottschalkThesis advisor: Shannon SeitzThis dissertation contains two essays in labor economics. It provides a descriptive analysis on income volatility and develops a microeconomic model to study how married couples make joint decisions in response to such income volatility. The first essay examines the recent trends in household income volatility in the United States, West Germany and Great Britain, and compares household income volatility with individual income volatility. I estimate a formal error components model using the Cross-national Equivalence File from 1979 to 2004. I find that household income volatility, measured by the transitory variance of household income, accounts for more than half of the total inc...