Urban areas have particular sensitivities to climate change, and therefore adaptation to a warming planet represents a challenging new issue for urban policy makers in both the developed and developing world. Further to climate mitigation strategies implemented in various cities over the past 20 years, more recent efforts of urban management have also included actions taken to adapt to increasing temperatures, sea level and extreme events.  Comparing existing experiences of several cities, we identify relevant levels of administrative adaptation planning, the tools and information used in making policy choices, and the roles of governance and finance in urban adaptation to climate change.

Important factors for successful adaptation planning include institutional assets such as good capacities for governance, participation in networks and personal engagement for this novel policy. On the physical side, we find less innovative solutions, as most measures for physical adaptation depend on traditional strategies for urban planning and infrastructure dimensioning. Zoning, urban greening, and realization of protection measures against erosion and flood surge represent the main part of urban adaptation activities, integrated by  “soft measures” for increasing resilience, such as insurance, early warning systems and capacity building.

Adaptation planning undertaken in the urban context, particularly related to infrastructures protecting against flooding and sea level rise (SLR), can be extremely costly and may require a long time horizon. Considering the high amount of values at stake, in economic, cultural and social terms, the protection of these values through adaptation must be considered a necessity rather than an option. As a consequence, the costs of measures of implementation are rarely considered. In those cases where economic criteria have been considered, cost-efficiency or cost-benefit criteria in adaptation planning have been observed having a twofold function: the calculations of potential benefits from adaptation can prove the economic viability of adaptation measures, providing thus a further trigger for starting adaptation processes, or on a different level, can provide support for decision making between different adaptation options and time horizons for implementation.