Over the past four decades, microfinance has grown from small local initiatives into a global phenomenon practiced in many markets, mostly in low-income economies but also in well-developed markets like the US and the EU. Interestingly, microfinance institutions (MFIs), that is, providers of financial services to end customers, often have several cross-border stakeholders, including shareholders, donors, lenders, and providers of technical assistance and advanced IT systems. Moreover, important “think tanks” like the CGAP provide the industry with global policy guidelines. Thus, microfinance is a very international industry and empirical evidence shows that international stakeholders as well as policymakers influence the performance of MFIs (Mersland et al., 2011; Mersland and Urgeghe, 2013). The purpose of this chapter is therefore to give an overview of the internationalization of the industry and to suggest relevant theories when studying cross-border microfinance partnerships. Moreover, we present initial statistical evidence of how internationalization can influence MFIs’ performance and the type of services they offer. Based on our initial results, we suggest a research agenda for future studies.