Since late 2006 the International Building Exhibition (IBA) Hamburg has made the concept of the “Leap across the Elbe“ a reality, and in doing so has provided considerable support for the urban, environmental and social development of the Elbe Islands and Harburg Upriver Port. Under its three key themes – "Cosmopolis", "Metrozones" and "Cities and Climate Change" – the IBA has also given real impetus to international discussions on the future of major cities. This book documents the projects carried out over the seven years, as well as novel approaches taken by the IBA, such as in the areas of education and participation pro-cesses, which will influence policy and everyday planning far beyond the end of the IBA in 2013. In addition, long-term partners of the IBA provide an initial summary of the current state of affairs.