The uncertainty of the future development of human life expectancy is probably larger than most people think. On the one hand climate change, pandemics, micro plastic, particulate matter in the air and many other trends imply a slowdown of the increase (or even a reduction) of human life expectancy. On the other hand, most medical experts agree that the mechanisms of aging are essentially understood and slowing down (or even reversing) aging is within reach. The talk gives a short overview over these aspects and concludes with a first attempt to suggest howag we could consider this uncertainty in understanding, modelling, measuring and managing longevity risk.