Development of a Global Sustainability Index for G8+5 Countries by Using TOPSIS Hisham Alidrisi Department of Industrial Engineering King Abdulaziz University Jeddah, Saudi Arabia hmalidrisi@kau.edu.sa Abstract It has been well established that sustainable development is a critical issue worldwide. Countries should consider the conservative consumption of available resources while maintaining their desired levels of economic growth. This study aimed to develop a global sustainability index for the Group of Eight + Five (G8+5) countries by using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The index is based on three criteria: the Gross Domestic Product, carbon dioxide emissions, and the World Happiness Index, which constitute the economic, environmental, and social dimensions, respectively, of sustainability. The results indicate that the TOPSIS has a competitive advantage over other multiple-criteria decision-making techniques. They also reveal the criteria weight sensitivity of the developed index. This suggests that policymakers and researchers should pay special attention to criteria selection and weighting. Keywords Global Sustainability Index, TOPSIS, sustainability, G8+5. 1. Introduction It has been well established that sustainable development (SD) is a critical issue worldwide. SD initiatives aim to meet the needs of current and future generations (Schaefer and Crane, 2005). This creates a dilemma for countries as they promote conservative approaches to resource consumption while maintaining their desired levels of economic growth. Therefore, in the past two decades, developed countries and many developing countries have sponsored SD initiatives (Bilgili et al. 2017, Borland et al. 2019, González et al. 2017, Majid 2020, Zhang and Wen 2008). Given that the Group of Eight + Five (G8+5) countries are either the most developed countries (Canada, France, Germany, Italy, Japan, Russia, the United Kingdom, and the United States) or the largest emerging economies (Brazil, China, India, Mexico, and South Africa), their initiatives are supposed to represent the ideal sustainable practices that can be benchmarked. Thus, this paper argues that the economic, social, and environmental data from these 13 countries could encourage researchers and policymakers worldwide to investigate and to benchmark SD initiatives. 1.1 Objective This study aimed to develop a global sustainability index for G8+5 countries by using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The developed index is based on three criteria: the Gross Domestic Product (GDP), carbon dioxide (CO2) emissions, and the World Happiness Index (WHI), which constitute the economic, environmental, and social dimensions, respectively, of sustainability. 2. Literature Review Mensah and Casadevall (2019) noted that although sustainability refers to the capacity to maintain “things” over time Proceedings of the International Conference on Industrial Engineering and Operations Management Sao Paulo, Brazil, April 5 - 8, 2021 © IEOM Society International 2340