||The dissertation contains three chapters. They cover the topics of household savings in economic development, relationship in the industry of investment banking, and the impact of globalization on urbanization, respectively. The first chapter, entitled " 'Keeping up with the Juniors'--- A Theory of Endogenous Savings in Economic Takeoff", provides a theoretical model trying to explain the noticeable and puzzling high household savings rates in rapidly growing economies such as China, Korea, Thailand, and Taiwan. The premise of the analysis is consumption externality of individuals' preferences, i.e., a person's preference for consumption in a period positively depends on that of an average consumer in the same period. Using an over-lapping generations model, the chapter shows that in a rapidly growing economy, under consumption externality, a consumer needs to save more in order to keep up with the consumption of the generation of his/her children (the juniors), since the young will earn more in the future and will consume more. Hence, in the steady state, the higher the growth rate, the higher the steady state savings rate. Also, a higher degree of the positive consumption externality will lead to a higher steady state savings rate. The second chapter is also a theoretical one, entitled "Relationship in Investment Banking --- An Incomplete Contract Theory." The chapter explains the existence and persistence of relationship in investment banking from an incomplete contract perspective. It shows that ex ante a firm that may need financial service in the future chooses to optimally commit to dealing with a limited number of investment banks. This induces the related investment banks to make necessary ex ante investments in order to serve the firm better. Subsequently, the investment bank designs its compensation contract optimally so that bonus is a major component of total pay to its employees. The chapter explains a number of puzzling observations in the industry of investment banking. The third chapter is an empirical study of the impact of GATT/WTO accession on urbanization. The title of it is "Does GATT/WTO Accession Accelerate Urbanization? --- Evidence from the World, 1960-1998." This chapter answers the question that whether and how GATT/WTO accession changes the pace of urbanization. Using a data set of 112 economies covering the years from 1960 to 1998, I showed that GATT/WTO accession had different impact on urbanization in high- and low-income economies. The rate of urbanization in high-income economies increased at a slower pace upon accession, while it had an extra annual increase in low-income economies upon accession. The slowing down of urbanization upon accession in high-income economies is found to be caused by less policy distortions due to enhanced openness and by decreasing shares of services industry in economic structure. On the other hand, the pouring-in of foreign investment due to the increased level of openness and the development of services industry after GATT/WTO accession in low-income economies were responsible for their speeding up urbanization pace.