The world is suffering from a housing-affordability crisis. Dezeen's new series will explore the Social Housing Revival, and celebrate the best contemporary social housing around the globe.

Last week, the UK Government revealed that at the last count, 109,000 households in England were legally homeless ? a 10 per cent rise on a year before ? while rough sleeping is 120 per cent more prevalent than it was in 2010.
These are but the latest in a long, long line of dismaying statistics about the suffocating housing-affordability crisis being experienced by people across the planet, particularly in major cities.
From London to New York, Dublin to Taipei, Lagos to Toronto, Sydney to San Francisco and many more places besides, a comfortable, affordable, secure home is simply out of reach for much of the population. A solution from the past
The consequences of this global crisis are profound. Poor quality, unaffordable housing is linked to physical and mental health problems, falling fertility rates, bad educational outcomes, civic discontent and inhibited economic growth. A growing number of commentators are even talking about "the housing theory of everything": the idea that the ripple effects stemming from a lack of affordable homes makes everything worse, for everyone.
It's a complex problem and opinions about the most significant root causes vary. Some point to population growth and urbanisation driving demand, others to a lack of new development due to planning law...