Possible solutions include opening national borders to millions of foreign migrant workers, raising retirement ages, requiring citizens to save more, and encouraging couples to have many more children.
Underlying the demographic crisis are two factors: people are living longer and birth rates have fallen to low levels. In Europe, the average age of the population has already climbed to 40, as healthier living, improved medical care and innovations in pharmaceuticals stretch longevity.
By 2050, the average is set to rise to 50. By mid-century, there will be 40 million Europeans aged 65 or over. At the same time, there will be fewer people of working age to support the elderly, thanks to falling birth rates. The average European woman now has fewer than 1.5 children.
Summit speakers called for less generous social security and increased saving by those at work, to provide for their own financial security and personal care in later life. Employers must also be encouraged to allow older people to carry on working under flexible conditions.