Digitalization can increase resource and energy productivities. However, the production and usage of information and communication technologies (ICTs) require materials and energy, and the application of ICTs fosters economic growth. This paper examines whether digitalization helps or hinders an absolute decoupling of environmental throughput from economic growth. The paper combines the literature on "green IT" and "ICT for green" with studies on decoupling, i.e., the relationship between economic growth, technological change, and environmental throughput. The paper identifies several strains of the decoupling debate and connects them to the environmental implications of digitalization. We focus on the relation between digitalization and (1) the question of finite non-renewable energies, (2) the environmental Kuznets curve, (3) the role of energy consumption for economic growth, (4) efficiency improvements vis-à-vis rebound effects, and (5) the role of general purpose technologies for resource and energy demand. We find that the empirical basis regarding digitalization's relation to these four aspects is still weak and hence, further research is needed. Comparing the mitigating and the aggravating impacts of digitalization, we conclude that a more active political and societal shaping of the process of digitalization is needed to make ICT work for global environmental sustainability. © 2020 by the authors.