1. Sustainable Urban Systems: A Review of How Sustainability Indicators Inform Decisions

The Brundtland commission defined sustainable development as: development that meets the needs of the present without compromising the ability of future generations to meet their own needs (Butlin (1989) Our common future, by World Commission on Environment and Development. Oxford University Press, London, 1987). Translating this definition into an urban context has led to a focus on the use of indicators and indicator sets to quantify sustainability and guide government and stakeholder decisions. Although sustainability assessment methodologies demonstrate a direct link between indicator use and decisions made, there is limited discussion on how indicators actually help decisions. In this review, we examine 22 applied urban sustainability studies to assess whether indicators foster decisions. The 22 studies were analyzed on six dimensions that play a role in indicator development and use: the indicators themselves, stakeholder involvement, geographic and cultural impact, framing sustainability, definition of urban, and decision-making. Our results show that the connection between indicators and their effect on decision outcomes is not considered in indicator development, and although decision-making is briefly discussed by most of the evaluators it is rarely explored in-depth. In addition, vague definitions of sustainability and urban, geographic and cultural diversity, and a lack of concrete measures of the social qualities of sustainability have hampered the ability of indicators to create holistic decisions. We conclude that indicators themselves do not foster decisions and must be applied within a broader framework that can incorporate social and perceptual issues with indicators, such as multi-criteria decision analysis. Otherwise, the lack of clarity found in sustainability assessment prevents substantive decisions to improve environmental, economic, and social qualities of urban systems.