The dissertation contributes to our understanding of how multinational firms and financial frictions affect income in developing countries. From a policy perspective, I find that as developing countries open up to multinational firms, financial reforms become increasingly beneficial to national income in the countries. I also find that the joint ventures of foreign multinational firms with state-owned firms, an industrial policy in China, prevent technology spillovers and suppress industrial output. The dissertation consists of three chapters. Chapter 1: Financial frictions, Multinational Firms, and Income in Developing Countries: Theoretical Analysis Financial frictions create resource misallocation across heterogeneous production units a...