How exactly is technology transforming us and our worlds, and what (if anything) can and should we do about it? Heidegger already felt this philosophical question concerning technology pressing in on him in 1951, and his thought-full and deliberately provocative response is still worth pondering today. What light does his thinking cast not just on the nuclear technology of the atomic age but also on more contemporary technologies such as genome engineering, synthetic biology, and the latest advances in information technology, so-called "generative AIs" like ChatGPT? These are some of the questions this book addresses, situating the latest controversial technologies in the light of Heidegger's influential understanding of technology as an historical mode of ontological disclosure. In this way, we seek to take the measure of Heidegger's ontological understanding of technology as a constellation of intelligibility with an important philosophical heritage and a dangerous but still promising future.