Emerging technologies are both a cause of many grand societal challenges (GSCs) facing twenty-first-century societies and an integral part of some of their most promising solutions. As an element of the GSCs, technology becomes intertwined with several interrelated issues that constitute the GSCs. This calls for approaches to Technology Assessment (TA) that account for the paradoxical role of technology in the GSCs, and the imperative and complexity of pointing technological innovation toward addressing the GSCs. In this introduction to the special issue, we identify three major streams in TA research and practice, namely TA as a policy instrument, a deliberation process, and an issue field. These streams highlight tensions between relying on experts and on the inclusion of various stakeholders in TA processes, and between a TA framing around the intersection of technology and critical issues around critical issues, such as those constituting the GSCs. We discuss the advantages and challenges of each stream. We also outline and discuss key principles for conducting TA in the context of GSCs. We end by introducing the four papers that constitute this special issue.@en