We need to understand sleep and circadian disorders at a more mechanistic level. This applies to both the pathogenesis of these disorders and to their impact on health. New neurobiological and molecular tools facilitate this research. The focus needs to be not only in brain but also the impact of these disorders on future of peripheral organs. The elucidation of the fundamental functions of sleep and the impact of sleep fragmentation on these functions opens up a new paradigm for research. This type of research will facilitate translational research.