Green Zones are an innovative policy to transform toxic hotspots into sustainable healthy neighborhoods. The concept was originated by grassroots environmental justice groups in California, with communities most impacted by pollution central to the policy development and planning processes. Specifically, areas where multiple pollution sources (“cumulative pollution”) are overburdening already vulnerable low income and communities of color are targeted. It is based on the fundamental principle that clean air to breathe and clean land are basic human right, and should not be determined by income and race. Green Zones focus governmental and local business resources toward a just transition plan for overburdened communities – where people have been exposed to the toxic effects of pollutants from heavy industry, factories, and busy highways – toward a healthy place and economy. The main components of Green Zones policies are to 1) do no harm; 2) reduce the existing burden; and 3) invest in communities.