The 2002 presidential elections marked a turning point in Bolivia's history. In a country with a large subsistent rural population, a social movement of peasant and indigenous peoples came within a mere one and a half percentage points of wresting control of the political power that had eluded them for over five hundred years. Three years later, Evo Morales was elected president, becoming the first indigenous leader of a rural social movement to govern in Latin America. From the political ecology perspective known as liberation ecology, this thesis examines how a social movement based largely in marginalized rural communities achieved a political victory unprecedented in the Americas. The research reveals that the development of a political "instrument", known by its acronym MAS, originated in the peasant organizations and reflects a fusion of threats and opportunities related to the "agrarian question", livelihood options and ethnic identity, all of these deepened by a neoliberal economic model that exacerbated the crisis of rural communities. Leaders of the MAS successfully mobilized peasant and indigenous organizations by reaching back to elements of their 'long' history--a history in which resilience, reciprocity, and resistance to a worldview not of their making figure prominently. Events in Bolivia provide evidence of the potential to launch a democratic, counter-hegemonic offensive to an unsustainable global system that disproportionately assigns human and environmental costs and benefits, between and within nations. A Sustainable Rural Communities (SRC) framework, because of its explicit incorporation of the social instrumentality implied by "community", and the possibility of constructing a counter-hegemonic meaning for "rural sustainability", provides an ideal conceptual lens through which to explore the potential for a shift toward alternative sustainable development. By building on Sumner's (2005) theoretical model of sustainability and introducing the dimension of political agency, this research provides a means for linking the theory and praxis of social movements with alternative perspectives on sustainability. In doing so, it represents a step toward further developing the theoretical foundation of liberation ecology, and political ecology more generally.