Due to the growing scarcity of natural resources and rising prices for energy and raw materials, multinational corporations are increasingly trying to access and gain control over the remaining resources – much of which are located in remote areas, often referred to as ‘frontiers’ – recently opened up to resource exploitation (McLellan et al. 2012; Yellishetty et al. 2012). As Rivero and Cooney Seisededos (2010: 57) explain, a ‘frontier’ is the border that divides a known or organised space from another space that is as yet unknown or viewed as worthy of exploration and exploitation. ‘More than just a theoretical concept, the frontier is a powerful metaphor that establishes the space of transformation, change, and conquest’. In order for a particular venture to be profitable, multinational corporations frequently need or require exclusive access to these resource-heavy areas; once obtained, the extraction processes are usually intense. Because gaining access to these areas and extracting the resources from them may displace groups of people already living in these areas or cause negative environmental impacts that adversely affect the survival of such groups, frontiers are often characterised by conflict and violence (Langfur 2006). This chapter discusses conflict over natural resources on three frontiers by examining the activities of mining companies AngloGold Ashanti and Gran Colombia Gold in Colombia and the case of the Belo Monte hydroelectric dam in Brazil.