Whilst increasing crop productivity and nutrient use efficiency are clearly major drivers in biofuel crop breeding plans, until now the question of biomass raw material quality has received little attention. However, it is clear that we need to focus attention on producing biomass feedstock that is tailored for biorefinery applications to produce fuels and other value products. This requires a focus on the composition and convertibility of lignocellulose in these crops, as well as accessing and developing the full range of valuable products and materials that might be generated from them. Sugar cane, maize and miscanthus are all important crops in the move to sustainable bioethanol production, and because they are all C4 grasses, they are united by close similarity in the composition and structure of their cell walls. C4 grasses are so-called because they have evolved a more efficient system for photosynthesis, which avoids the inefficiencies that arise through photorespiration, and are generally the most productive crops available. Brazilian bioethanol production is focussed on sugar cane due to the high yield of sugars that can be readily fermented, but this tropical crop is unsuitable for growth in Europe. Maize is a major crop grown mostly for grain in many areas of the world including Europe and Brazil. One of the other major biomass crops being developed is the perennial C4 grass miscanthus. Because these three crops are close relatives of one another there will be great synergies and transferability in working on all three.