In cities where the line between safety and danger can be invisible, those who have learned to read urban environments offer a quiet but vital form of wisdom. Security professionals, transit workers, and long-tenured residents of high-crime neighborhoods share a common discipline: deliberate, present-minded attention to the world around them. Their counsel is not rooted in fear, but in the ancient human practice of knowing one's surroundings — a skill as old as survival itself, now applied to sidewalks, transit stations, and unfamiliar streets.