Miscanthus is a rhizomatous C4 grass that has the potential to produce high biomass yields over a wide geographical area with low agricultural inputs on land less suitable for food production. Miscanthus x giganteus is a naturally occurring hybrid genotype which has been widely cultivated and studied in Europe for more than 20 years. Novel hybrids are expected to increase yield and reduce biomass production costs in a range of climates through cheaper propagation, lower inputs, reduced risk of crop failure in climatic extremes or through disease, make harvesting and storage easier and improve fuel quality traits. An international Miscanthus breeding programme led by IBERS with public and private partners has been built up since 2004. Phenotypic and genotypic characterisation of wild and hybrid germplasm at multiple locations is being used to guide selections and crosses. Genomics and marker assisted selection are being developed for long term breeding. Underpinning science in BSBEC has shown that heterosis in the interspecific hybrids such as M. x giganteus increases in net photosynthetic carbon assimilation efficiency up to 40% in the UK climate. Although clone based hybrids have been key to recognising Miscanthus’ biomass potential, interspecific hybrid seed enables rapid scale up of the crop and will reduce establishment costs, once proven and seed-based agronomies are ready to be deployed.