177 million tonnes of virgin aggregates, 15 million tonnes of cement and 2 billion bricks were used to build houses, civic and commercial buildings, roads and railways, etc, in the UK in 2016. Meanwhile, 64 million tonnes of waste arose from construction and demolition. Materials from construction and demolition are mainly managed by down-cycling with loss of the value imparted to them by energy-intensive and polluting manufacturing processes; for example, high value concrete is broken down into low value aggregate. Environmental damage is associated with the whole linear life cycles of mineral-based construction materials, and includes scarring of the landscape and habitat destruction when minerals are extracted from the earth; depletion of mineral and energy resources; and water use and emission of greenhouse gases and other pollutants to air, land and water, during extraction, processing, use and demolition. It is important to take action now, to return materials to the resource loop in a Circular Economy, and reduce the amount of extraction from the earth, as the amount we build increases each year. For example, the UK plans spend £600 billion to build infrastructure in the next decade. The UKRI National Interdisciplinary Circular Economy Research Centre for Mineral-based Construction Materials therefore aims to do more with less mineral-based construction materials, to reduce costs to industry, reduce waste and pollution, and benefit the natural environment that we depend on. There is potential for mineral-based construction materials to be reused and recycled at higher value, for example, by refurbishing rather than demolishing, or by building using reusable modules that can be taken apart rather than demolished, so all the energy that went into making them isn't wasted. It may also be possible to substitute minerals from natural sources by other types of mineral wastes, such as the 76 million tonnes of waste arising from excavation and quarrying, 14 million tonnes of mineral wastes that come from other industries, or 4 billion tonnes of historical mining wastes. We can also be more frugal in our use of mineral-based construction materials, by designing materials, products and structures to use less primary raw materials, last longer, and be suitable for repurposing rather than demolition, and using new manufacturing techniques. First, our research will try to better understand how mineral-based construction materials flow through the economy, over all the stages of their life cycle, including extraction, processing, manufacture, and end-of-life. The Centre will work to support the National Materials Database planned by the Office of National Statistics, which will capture how, where and when materials are used and waste arises, so that we have the information to improve this system. We will also study how any changes we might make to practices around minerals use would affect the environment and the economy, such as greenhouse gas emissions, costs to businesses, or jobs. Second, we will work on technical improvements that we can make in design of mineral-based products and structures, and in all the life-cycle stages of mineral-based construction materials. Third, we will look at how changes in current business models and practices could support use of less mineral-based construction materials, such as how they might be able to move more quickly to new technologies, or how they might use digital technologies to keep track of materials. We will explore how the government can support these changes, and how we can provide education so that everyone working in this system understands what they need to do. In the first 4 years of our Centre, 15 postdoctoral researchers will gain research experience working in the universities for 2y and will then work with an industrial collaborator for a year, to implement the results of their research. More than 20 PhD and 30 MSc students will also be trained in the Centre.