Even though the ICT (Information and Communication Technology) industry has historically been spared the critique of being environmentally unfriendly, society has as of late recognised the negative environmental effects of the ICT industry. However, such critique has been gradually replaced by the concept of Sustainable ICT, in which ICT is almost seen as a saviour, something with big potential of solving economic, societal and environmental issues. In this paper, our aim is to critically discuss the notion of Sustainable ICT by turning to an ecological perspective of World Systems Theory (WST). Immanuel Wallerstein, the main proponent of WST argues that the success of developed (core) countries today is a product of systematic unequal exchange of raw material, goods and labour with underdeveloped (peripheral) countries. Alf Hornborg, the Swedish Marxist ecologist, develops WST by focusing on the global distribution of environmental degradation. In this paper, we present Hornborg’s ecological WST, we apply it to ICT by means of examples from the ICT Value Chain (from materials extraction to disposal) in order to illustrate the global distribution of environmental degradation. We argue that WST is a fruitful, and critical, alternative perspective to the more optimistic view of Sustainable ICT.