The International Typographic Style, developed primarily in Zurich and Basel in the 1950s, is the most successful design movement of the twentieth century by any measure of influence. It conquered corporate identity, magazine layout, wayfinding systems, and poster design with a thoroughness that would be remarkable even if its formal prescriptions had been arbitrary — which they were not. The Swiss style solved real problems, and its solutions were good enough that they became defaults, and its defaults became invisible, and its invisibility is now so complete that most people cannot see the infrastructure it built.