Developing a framework system for sustainability performance of cities: a case of Eskisehir city, Türkiye

This study aims to facilitates sustainable city assessment, which is extremely useful yet intricate, to evaluate sustainability of cities through the identification of both their strengths and areas that can be further improved. For this purpose, an easy-to-apply assessment framework was established, and a practical tool in MS Excel was developed using the framework. The framework consists of defining objectives, determining indicators, weighting the indicators, collecting indicator data, scaling, and normalizing indicator values, and calculating and evaluating the sustainability performance of cities. In this study, an indicator set was created using forty-five criteria aligned with the triple-bottom-line sustainability categories. The indicator set was weighted through a questionnaire study with experts, followed by a scaling study using minimum–maximum data values for normalization. Subsequently, criteria scores were calculated and aggregated within sub-indicators to assess sustainability performance of cities. A case study was conducted in Eskisehir city and its results were compared to average value from eighty-one cities in Türkiye. The results indicate that Eskisehir’s sustainability performance for indicators- environmental at 68%, social at 74%, and economic at 66% -yields an overall weighted average of approximately 69%, with the best performance in social indicators and the lowest in economic indicators. This study contributes to by developing of a globally applicable framework for city sustainability assessment. It enables individual evaluation of cities based on their sustainability goals and provides a practical tool for assessing urban sustainability performance. The findings provide key insights for guiding investments and policy decisions, supporting evidence-based approaches for researchers, stakeholders, and investors. The tool’s implications for urban development include improving air quality, waste management, economic growth, and social justice, making the study highly relevant for sustainable urban futures.