In this thesis, I first investigate the relation between the aggregate unemployment rate and foreign direct investment (FDI) inflows and outflows. To study this relationship, I use a panel data set that contains 45 (developed and developing) countries observed from 1987 through 2008, and I employ Arellano and Bonds generalized methods of moments (ABGMM) estimation method for dynamic panel data. My results show that FDI inflows and outflows are not determinants of the aggregate unemployment rate. In addition, in line with macroeconomic theory, the previous level of aggregate unemployment has a positive impact on the current level of aggregate unemployment. Again, as macroeconomic theory suggests, my results show that per capita real gross domestic product (RGDP) has a negative effect on the current level of aggregate unemployment. Second, I study the long-run relationship between exports and per capita gross domestic product (instrumented by total population) using a panel data set of 51 countries from 1970 through 2008. To study this relationship, I employ the dynamic ordinary least squares (DOLS) estimation method. I find that the percentage of exports in nominal gross domestic products (GDP) is sensitive to changes in the populations of host countries and, hence, to the changes in their GDP. In addition, my results show that the agreement on trade related investment measures increased the percentage of exports in the nominal GDP of developed host countries more than it did in developing host countries.