Ageing is a phenomenon which is becoming one of the leading priorities of Europe and of the European Commission. The ageing of the population of Europe is a fact which is evident given the trend towards healthier, more active and longer lives. There are four main demographic trends (EC, 2006), specifically the average number of children per woman is below the population replacement number of 2.1 per woman for industrialised countries, and this rate is falling further; the decline in fertility in recent decades followed the post-war baby boom which is today causing the bulge in the size of the population aged 45 to 65 years; the dramatic increase in life expectancy since 1960; and the fact that immigration, although primarily of working age, will not compensate for the joint effect of low fertility and increased life expectancy. More generally, ageing, as emphasized by EC communication on Disability Action Plan (2005), is strongly correlated with disability prevalence: nearly 30% of people belonging to the age group of 5564 report a disability and 63% of people with disabilities are older than 45. This is the so-called phenomenon of compression of morbidity. There is a need to measure these elements independently and against the background of the clear conceptual framework of health provided by WHO's International Classification of Functioning, Disability and Health ICF (WHO, 2001; Leonardi et al., 2006). Based on a theoretical framework that defines disability as the interaction of a health condition with contextual factors, ICF has been tested since its approval in 2001 in several projects, such as the EU project MHADIE (www.mhadie.it). Taking all this into account, including the notion that the UN Convention on the Rights of Persons with Disabilities that mandates the need for clear data as an essential precondition for rights-based policy (Art 31), the Collaborative Research on Ageing in Europe (COURAGE in Europewww.courageineurope.eu) attempts to respond to this need by developing an ICF-based instrument for measuring health, health-related outcomes and determinants of disability for an ageing population.