Our world is becoming more unsustainable. Information on existing sustainability can be used for future development planning. This study presents an approach for quantify and measurement of urban sustainability. Delphi and fuzzy logic methods were the discovery techniques used. The city system comprised social, economic and environmental subsystems. Seven orientors, consisting of existence, effectiveness, freedom of action, security, adaptability, coexistence and psychological needs were measured by different indicators. The final sustainability output was obtained by aggregation of the multiple orientor and subsystem sustainability values into a unified measure. A Fuzzy Sustainability output was developed for comparing the importance of sustainability orientors and subsystems. The model was applied to Mahshahr, a coastal industrialized city in Iran. The model output for the three subsystems was able to show significant differences between the economic and environmental subsystems, each, and the social subsystem. The final sustainability output showed that the effectiveness orientor gave the highest sustainability value. The model is dynamic and can be modified for different purposes by changing indicators. With this model, policy makers can evaluate existing city sustainability and project the future sustainability by varying the indicators. This can be carried out at local, regional and global scales for security and adaptation strategies, mitigation plans, and overall sustainable development manage.
Decision Making; Orientor; Sustainability; Shadegan wetland; Unified measurement;