This chapter uses the rise of Carnegie Steel as a case study to explore the social and economic context of materials innovation. In the United States during the 19th century, steel became a vital element of industrial growth, and Andrew Carnegie revolutionized its production through a system of hard driving at his steel mills outside of Pittsburgh, Pennsylvania. This is an example of the economic theory of creative destruction, in which innovation in technology and the organization of the shop floor replaces long-standing institutions and practices in the production of materials. As a result, there are both gains to society—in this case cheap steel for the construction of things like buildings and railroads, as well as drawbacks for workers and companies that tried to compete with Carnegie. In summary, innovation in the manufacture of materials can be a double-edged sword.