The suntan experienced a profound change in the last century. Considered a mark of the lower class for hundreds of years, tanning became a fad in the early 1920s and remains popular today. The tan, though, was much more than a matter of fashion,enjoying at first a boost from the medical establishment. Opinions ranging from hard science to quackery lauded the suntan as something of a panacea. Near the end of World War II, however, researchers increasingly warned against the hazards of overexposure to the sun, and a large new industry developed—sunscreen. Americans' current paradoxical obsession with the tan developed almost entirely from the conflicting rays of twentieth century thought. This history examines the twentieth century suntan as a social and scientific phenomenon. Beginning with the years 1900-1920, it debunks the myth that changing attitudes toward the tan sprang largely from the world of fashion. Initial pro-tanning medical hype, emerging negative opinions of sunbathing near the middle of the century, the development of sunscreens, the debate over sunscreen efficacy, and the sunless tan are all covered here. Numerous pictures demonstrate changing perceptions of the suntan, displaying advertisements for products that promoted, prevented or healed tans.