Miami Grand Central Park is a new model for privately-held public space on the blighted former Miami Heat Arena site in downtown Miami. It was conceived as a multi-use, transformable, open platform for community events, corporate picnics, musical performances and festivals. A typical day in the life of Grand Central Park begins with an organic farmers’ and artisans’ market in the morning; then the plaza space generates revenue by operating as overflow parking during the work day. At sunset it often serves as an impromptu concert or lecture venue, and it can be converted to a drive-in and bike-in movie theater at night. Permanent amenities including paths, benches and a sculpture garden provide much-needed passive recreation space for the downtown district. Future plans also include a skateboard park, an open-air ice rink during the holiday season, and a movable wave machine for surfing in the summer. Operationally, the site has been designed for financial and infrastructural independence from the city, so that it is a catalyst for change rather than a burden. It was built with a labor force composed in equal parts of employed local homeless and volunteers. The plantings recall the native habitat that existed before the city of Miami was developed, and rubble from the former arena has been recycled to form a superscale berm that organizes the site. Bypassing the need for city water or storm sewers, all rainwater is captured and cleaned for irrigation; in turn this low-pH water facilitates efficient nutrient uptake for the trees and eliminates the need for chemical fertilizers.