In the Upper Bay of New York’s harbor, there is a new urban island under construction. Technically, this project is a work of rejuvenation or, as professionals say, adaptive re-use. A military installation since colonial times, Governors Island hosted a U.S. Army base until the mid-1960s. Then the Coast Guard took over, operating there until 1997, when the federal government deeded the island to the City and State of New York. Good timing. The subsequent fifteen years saw New York City’s most radical re-invention since the invention of the elevator.