Today’s industrial societies offer their citizens comfort and ease, jobs and leisure, as well as an appropriate infrastructure. At the same time, the modern living environment is transforming into a warehouse brimming with precious raw materials that are coveted by industry. But just how big is the resource depot we live in? Which material flows feed it? Where can precious materials be extracted and re-used? The – or at least one – solution to the problem lies in closed material cycles: everything keeps getting recycled, is broken up into individual parts, given a new form, revalued and re-used. This is the focus of the current issue of EmpaQuarterly. Whether in the construction sector or as electrical waste, the materials lying dormant in the “urban mine” are simply too precious to be thrown away.