In some countries public pension systems are accumulating large reserve funds to complement pay-as-you-go financing. This chapter presents the main trends in assets and investments of these funds up to December 2007. The 2008 financial crisis has had a major impact on the value of some of these funds as their equity allocations had been rapidly increasing in recent years. However, some of these funds have an even longer investment horizon than pension funds, especially in those countries where by law they are not expected to make any disbursements for the next ten to twenty years. Hence, these funds can take larger risks than most pension funds in the expectation that over the long term the investment strategy will pay off. This chapter contains data and analysis on public pension reserve funds (PPRFs) which are defined as funds set up by governments or social security institutions with the sole objective of complementing the financing of pay-as-you-go (PAYG), public pension plans.