This study outlines and compares the possible ways of reforming modern, pay-as-you-go (PAYG) pension systems – reforms which are necessitated by unfavourable demographic processes. This comparison is made in a general context and the examination does not focus on any specific country. Pension reform ideas usually stay within the pension paradigm outlined by Samuelson (‘AI scenario’). While also describing these approaches, the study points out – citing lesser-known ideas in this context – that there are several ways out of the situation. [---]