Long before Baron Haussmann remade Paris, several generations of intellectuals, planners, architects, engineers, and politicians envisioned a radical transformation of medieval Paris into a modern city that would be beautiful, rational, sanitary, and responsive to the needs of commerce and industry. Historian Nicholas Papayanis examines the emergence and evolution of modern urban planning in Paris between the end of the eighteenth and the middle of the nineteenth century, focusing on the principles and concerns that informed competing plans for the city.