This paper provides new projections on the fiscal impact of age-related spending for OECD countries over the next half century. These results are based on national models using an agreed upon set of assumptions about macroeconomic and demographic developments for all countries. Recent reforms to pension systems have partly offset the impact on spending of an increasingly elderly population, and there has been a major improvement in the underlying fiscal situation in the 1990s. However, further age-related spending (including old age pensions, health and spending associated with children) is still projected to increase on average around 6 to 7 per cent of GDP over the projection period. This calls for maintaining the reform effort and intensifying it in several countries, if fiscal sustainability is to be maintained ...