How ‘single exit stairway’ buildings could make cities better and safer

Before sitting down in my consulting room, Matt A. stepped forward and shook my hand. He was an athletic and handsome forty-seven-year-old man. He wore a white cashmere sweater, black Chelsea boots, and tortoiseshell glasses. His red watchband matched his socks. Typically, people who come to see me for a consultation begin by describing a problem; Matt began by describing himself. He told me that he worked in Downing Street as a political strategist and consultant for then British prime minister Tony Blair. This was 1999. He had been married for twenty years and had three teenage...