This special issue of Network Industries Quarterly is dedicated to the greening of infrastructure assets. Despite the unprecedented challenges brought about by the COVID-19 pandemic, the European Commission has reaffirmed its commitment to the objectives of the European Green Deal and to transforming Europe into the first climate neutral continent by 2050. Delivering this ambition will necessitate the revision of regulatory and taxation frameworks, as well as the deployment of clean and innovative technologies. These, in turn, will have to be supported by massive public investments and increased efforts to direct private capital towards climate and environmental action while avoiding lock-in into unsustainable practices and infrastructures. Though the specific approaches to ‘greening’ of infrastructure assets may vary across the network industries, a set of questions pertaining to technology, regulation and funding will have to be addressed in all of them. In this issue of the Network Industries Quarterly, our invited contributing authors critically examine these questions by drawing on the specific challenges and opportunities faced by the transport sector, as illustrated by the specific cases of airports, railways and ports.