The problem of climate change is high on the various political-administrative agendas, both national and international. At the same time the problem is full of uncertainties and controversies. Adaptation to climate change asks for adjustments in our spatial planning, but can also necessitate changes in the distribution of public and private responsibilities. A crucial question is how the legitimacy of adaptation measures can be organized in a context surrounded with uncertainties, controversies and conflicting interests. In this paper we introduce the central theme of this special issue and the various contributions.