Previous generations of animal scientists were extremely successful in increasing livestock production. Surpluses in Europe led us to focus more on other aspects of production systems – such as product quality, environmental effects and animal welfare -in the last 15 years. The recent FAO report ‘Livestock’s Long Shadow’ (FAO, 2006) has reinforced issues about pollution, greenhouse gases and loss of biodiversity associated with the production gains. They estimate that livestock lead to 37% of global methane and 65% of global nitrous oxide, whilst contributing 18% of global climate change. Recent dramatic increases in commodity prices for food, particularly milk protein, remind us of the need to increase productivity to meet the demand from increasing urban populations and compensate for losses to other land uses. The challenge is to develop systems that produce more and better food whilst also reducing pollution potential.