Street Medicine: Creating a "Classroom Without Walls" for Teaching Population Health.

"Street Medicine" programs provide medical care to homeless populations outside of traditional healthcare institutions, literally on the street and in transitional settings where unsheltered homeless people live. Such programs are emerging around the world often based at medical schools and primary care residency programs, and can provide ideal frameworks for twenty-first century "Classrooms Without Walls" aimed at improving Population Health. We provide a 12-step blueprint for creating a Street Medicine program in the context of a medical teaching institution.