GeopolyConc will provide the necessary scientific basis for the prediction of the long-term durability performance of alkali-activated ‘geopolymer’ concretes. These materials can be synthesised from industrial by-products and widely-available natural resources, and provide the opportunity for a highly significant reduction in the environmental footprint of the global construction materials industry, as it expands to meet the infrastructure needs of 21st century society. Experimental and modelling approaches will be coupled to provide major advances in the state of the art in the science and engineering of geopolymer concretes. The key scientific focus areas will be: (a) the development of the first ever rigorous mathematical description of the factors influencing the transport properties of alkali-activated concretes, and (b) ground-breaking work in understanding and controlling the factors which lead to the onset of corrosion of steel reinforcing embedded in alkali-activated concretes. This project will generate confidence in geopolymer concrete durability, which is essential to the application of these materials in reducing EU and global CO2 emissions. The GeopolyConc project will also be integrated with leading multinational collaborative test programmes coordinated through a RILEM Technical Committee (TC DTA) which is chaired by the PI, providing a route to direct international utilisation of the project outcomes.