Energy and its role in development and modernity is surprisingly understated in the social sciences despite its socio-economic importance and the challenges identified in the previous chapter, such as poverty, pollution, environmental degradation and climate change. This chapter reviews the extant social science literature that relates to the triad of energy, modernity and sustainability. Specifically, it focuses on four different bodies of literature: socio-technical transitions, Ecological Modernisation Theory, energy practices, and political ecology.