Within the context of an exploration of the recent financial geographies literature, which laments the lack of attention paid to the dynamics and impacts of financial globalisation in Latin America and the global South, this paper examines the links between exclusion from formal financial services provision for low-income sectors across Latin America and the unstable nature of regional financial services architecture and economies. The paper examines a range of issues, including control of the financial services infrastructure by foreign corporations, the role of regional elites and (as importantly) the decision making processes of the poor themselves. This contextual analysis is employed to investigate the premise that the future sustainability of Latin American economies and societies more than ever depends on what efforts are made to develop the extension of financial services provision for the excluded and in so doing broaden the complexity, increase the heterogeneity and enhance the stability of the region's economies. To this end, the paper outlines the technical and non-technical barriers to banking the unbanked in the region within the context of an engagement with the dynamics of the radical changes in the international financial services sector that have impacted upon the region over recent years.