In 40 years from now, approximately 70% of the world’s population will live in cities. This strong urbanisation trend has an effect on the environment and intensifies pressure on natural resources. Growth will be particularly evident in cities in deltas, which will also face additional pressure as a result of climate change, land subsidence and sea-level rise. Cities worldwide are facing the challenge of becoming increasingly robust, resilient and sustainable. Urban stakeholders, both public and private, need a picture of the potential problems, effective solutions and action strategies.