AbstractThis paper argues that democratic collectives have reason to increase the voting power of their younger members. It first presents an intuitive case for weighted voting in general, before drawing support from a prominent principle of democratic inclusion – the all-affected principle. On a plausible understanding of that principle, a decision may affect people to varying degrees, and this variation should be reflected in the strength of their say. The paper then argues that exposure time to a decision’s effects is typically a good proxy for tracking such variation, such that collectives have reason to gradually reduce their members’ voting power as they grow older. This holds, for example, in the ordinary parliamentary elections in representative democracies. It is then argued that we may build a similar case for age-weighting on a plausible version of the all-affected principle’s main rival, the all-subjected principle. The paper ends by addressing various objections. It argues that none of them undermine the case for age-weighting, and that some might even support age-weighting over its non-weighted (‘one person, one vote’) alternative.