Data power is a highly ambivalent phenomenon and it is precisely these ambivalences that open up important perspectives for the burgeoning field of critical data studies: First, the ambivalences between global infrastructures and local invisibilities. These challenge the grand narrative of the ephemeral nature of a global data infrastructure and instead make visible the local working and living conditions, and resources and arrangements required to operate and run them. Second is the ambivalences between the state and data justice. These consider data justice in relation to state surveillance and data capitalism and reflect the ambivalences between an “entrepreneurial state” and a “welfare state”. Third is the ambivalences of everyday practices and collective action, in which civil society groups, communities, and movements try to position the interests of people against the “big players” in the tech industry. With this introduction, we want to make the argument that seeing data power and its irreducible ambivalences in a pointed way will provide an orientation to the chapters of this book. To this end, we first give a brief outline of the development of critical data studies. In part, we also want to situate the data power conferences, the most recent of which this volume is based on. This will then serve as a basis for taking a closer look at three facets of the ambivalence of data power.