In the Division of Energy Balance and Obesity our aim is to investigate the genetic basis of the fundamental biology that underlies our feeding behaviour and energy expenditure, with a view to designing interventions to alleviate obesity that work in the knowledge of a persons genetic constitution. We envisage in the medium to long term that it will ultimately be possible to identify specific genetic problems that underlie many of the observed cases of obesity and it will be possible to treat patients individually according to the nature of their specific problem. Our long term goal is to develop such treatments and hence make an impact on the global problem of obesity. It should be borne in mind that the magnitude of this problem is such that even if we have only a marginal success the benefits will be enormous. If we were to reduce the prevalence of obesity in the UK, for example, by only 4%, the positive impact on the UK economy would be £100 million per year.