In an age of rising global environmental concerns, cities have come to play a key role in managing environmental issues such as climate change and food security on more regional and local scales and thus have become the locus for sustainable development. However, while sustainable urban development is perceived as a consensus-based planning approach that is beneficial to all and politically neutral, in practice sustainable development practices can be contested due to a raised emphasis on economic and environmental imperatives, whereas social objectives become increasingly neglected. The purpose of this dissertation is to provide a critical analysis of sustainable urban development practices using the process of environmental gentrification as an analytical tool to shed light on the possible negative social outcomes of the drive for sustainability in Berlin, Germany. The two main objectives are; firstly the detailed elaboration of the concept of environmental gentrification and secondly the examination of the extent to which gentrification processes in Berlin have been fuelled by environmental urban policy. It will be argued that it is necessary to recognize the contradictions and conflicting objectives of urban environmental policy, in order to more effectively manage cities and ensure sustainable urban development.