California has such a huge undersupply of housing -- and oversupply of housing speculators -- that affluent homebuyers have effectively rendered the state's major cities unaffordable for all but the very wealthy, even pushing into neighborhoods that were historically undesirable due to poverty, poor housing stock and crime. As a result, everyday working people are being pushed out of cities, and they're clustering in suburbs and exurbs around the cities' peripheries, creating both a traffic crisis (California's roads are already massively overcongested) and a housing crisis for those communities, with rents going up and up as new tenants arrive, having been pushed out of the cities. Many working California families are now on a "financial knife edge," one minor blip away from homelessness -- a tiny rent increase or a medical emergency or an unexpected car repair can spell eviction. The state has enacted sweeping rent controls that go into effect Jan 1, but these will not adequately address the state's housing crisis: California needs a lot of high-density housing clustered around high-speed transit lines.