Many have arrived on the streets just recently, victims of the same prosperity that has transformed cities across the US West Coast. As officials struggle to respond to this growing crisis, some say things are likely to get worse.
Vibrant Portland, Oregon's largest city, has long lured many. It is the City of Roses, of pleasant climate, rich culture and progressive thinking. It is also an innovation hub, part of what is called Silicon Forest, and new residents have moved here in these post-recession years attracted by its high-tech companies and their well-paid jobs.
But the bonanza, unsurprisingly, has not come to everyone.