This dissertation consists of four empirical chapters where I investigate the drivers of trade and migration within a country as well as examine the phenomenon of subnational income convergence and economic growth across countries. In Chapter 2 I estimate the size and pattern of barriers to the interprovincial trade in Canada. I simultaneously study how several regional agreements in place to eliminate those barriers impact trade within Canada. Using a panel of the Canadian provinces I find that most of these agreements have increased provincial trade whereas a couple of those deceased it. Also, there were large barriers to interprovincial trade that moderately decreased by 9.2 percent over a span of two decades in Canada. In Chapter 3 I measure the magnitude and pattern of barriers to the interprovincial migration in Canada. At the same time, I examine how various interprovincial agreements that have been negotiated to curb those barriers, influence the aggregate migration flows within Canada. I find that the average barriers to the interprovincial migration are larger than was previously estimated and are about one fifth the size of the average barriers to trade within Canada. Meanwhile the aggregate interprovincial migration responded perversely on average to the agreements examined. In Chapter 4 I explore what factors underlie the individual migration behaviour in Canada. I find that wage differentials, regulatory barriers, interprovincial agreements, and other explanatory variables had statistically significant but empirically small effects on the interprovincial migration of individuals. Finally, in Chapter 5 I investigate the per capita income convergence phenomenon as well as the determinants of the observed convergence pattern across the subnational jurisdictions in the North American Free Trade Agreement-NAFTA countries. I find that the poor jurisdictions grew faster than the rich ones and there was a decline in their income disparities after NAFTA. However, in the long run the jurisdictions converged either weakly or strongly in terms of their income growth under the various clubs that they formed both pre and post NAFTA. Such club formation was influenced by the initial conditions, structural and geographic characteristics some of which could be leveraged through government policies.