This report analyses the characteristics of ‘good density’ and begins to quantify the relation-ship between these characteristics, investor returns, and carbon emissions. We found that cities with good density – that is, dense development thoughtfully designed to promote a high quality of life – are likely to be more resilient and prosperous in the long term, and there-fore more likely to provide sustainable returns for investors, than cities without good density. Based on a quantitative analysis of 63 global cities, the report finds that cities with good density are associated with higher returns, capital values, and levels of investment flows for commercial real estate. The research provides evidence of important issues for the long-term resilience of cities both in the OECD and in fast-growing developing regions