In an increasingly urban society, city residents are finding innovative ways of stewarding nature that integrate environmental, community, and individual outcomes. These urban civic ecology practices – including community gardening, shellfish reintroductions, tree planting and care, and “friends of parks” initiatives to remove invasive and restore native species – generally begin as small, self-organized efforts after a prolonged period of economic and environmental decline or more sudden major disruptions, such as earthquakes, hurricanes, and conflict. Those practices that are sustained expand to encompass partnerships with non-profit organizations; local-, state-, and federal-level government agencies; and universities. Civic ecology practices reflect local cultures and environments as well as the practical knowledge of city residents, and thus vary widely across different cities. When viewed as local assets in some of the most densely populated urban neighborhoods, civic ecology practices offer opportunities for scientific and policy partnerships that address the Ecological Society of America's important Earth Stewardship initiative.