Architect Ole Scheeren is fed up with the rigid, hierarchy of the skyscraper. He hopes his buildings will change the way we think about soaring towers.

Supertall buildings have become just another part of the urban scenery. They are, writes science fiction writer Bruce Sterling, “stunningly factual, immediately obvious, impossible to overlook.” But what of the unbuilt towers of the future? What might *they* look like. With his customary lyricism, Sterling describes four classes of future skyscraper.