The 21st century will bring about chaotic environmental issues that are likely to be challenging and which will need innovative solutions. As one of these challenging issues, this study focuses on the at-risk coastal megacity of Istanbul and examines the role of the landscape architecture within the multidisciplinary structure of disaster management. This study includes two of the most at-risk southern coastal districts of Istanbul: Bakirkoy and Kadikoy, and evaluates their open spaces for emergency response by utilizing GIS technology. The evaluation process developed within this study constitutes six phases: examining the landscape and its changes, detecting current urban elements, eliminating unavailable urban elements for emergency response, defining open space and cluster types for the post-earthquake period, assigning clusters and open spaces, and defining strategies. This study highlights the importance of urban open spaces that are planned and designed in a disaster sensitive way for a more effective emergency response. By examining two at-risk coastal districts of Istanbul, this study develops a disaster sensitive planning approach toward the emergency response period, which will enable the generation of long-term disaster sensitive landscape strategies. This study is an attempt to further disaster sensitive landscape studies in the belief that coastal megacity of Istanbul will benefit from them.