The dissertation consists of three distinct chapters that contribute to important, yet unresolved topics in Macroeconomics and International Economics. Macroeconomists have been puzzled by the lack of a downward trend in per capita labor hours. The first chapter provides an explanation to the puzzle based on improvements in the quality of jobs over time. Through regressions analyses using data from the Michigan Health and Retirement Study, the chapter documents the response of work hours to improvements in the nature of jobs. An estimation of the aggregate job quality index suggests that improvements in jobs accounted for at least 20.4 percent of labor hours growth between 1850 and 2000 in the United States. A general equilibrium analysi...