Book excerpt: People have always grown food in urban spaces—on windowsills and sidewalks, and in backyards and neighborhood parks—but today, urban farmers are leading an environmental and social movement that transforms our national food system. To explore this agricultural renaissance, brothers David and Michael Hanson and urban farmer Edwin Marty document twelve successful urban farm programs, from an alternative school for girls in Detroit, to a backyard food swap in New Orleans, to a restaurant supply garden on a rooftop in Brooklyn. Each beautifully illustrated essay offers practical advice for budding farmers, such as composting and keeping livestock in the city, decontaminating toxic soil, even changing zoning laws.