Major progress in understanding 3 2.1 Adequacy from the perspective of the pension system 3 2.2 Adequacy from the individual/ household perspective 5 2.3 Retirement planning, information about pensions, and financial literacy 8 3 Remaining gaps in knowledge: main challenges 10 3.1 Understanding saving behaviour 10 3.2 A "smorgasbord" of open issues 11 4 Current state of play of European research infrastructures and networks 12 5 Required research infrastructures, methodological innovations, data, networks, and consequences for research policy 14 5.1 Data requirements 14 5.2 Methodological innovations required 16 6 What (and when) can we deliver on policy questions? 16 7 References 17