Ageing is a particularly demanding process to study, since its mechanisms are multiple, complex, highly interactive, and often stochastic in nature. Indeed, a barrier to progress has been the coexistence of multiple, seemingly competing hypotheses. The challenge is therefore to identify how to create the necessary joined-up understanding of the complex mechanisms of ageing in ways that will expose targets that might help to postpone age-related ill health and support healthy ageing. The intrinsic malleability of the ageing process, as revealed by current work, suggests that this goal is certainly attainable although it will require a major expansion in research volume if we are to reach it. Since age is the single biggest risk factor for a very wide spectrum of diseases, which individually attract major research effort, the prize of identifying exactly why aged cells are more vulnerable to pathology, and thereby how such pathology might be delayed or prevented, seems eminently worthwhile.