How did birth control become legitimate in the United States? One kitchen table at a time, contends Trent MacNamara, who charts how Americans reexamined old ideas about money, time, transcendence, nature, and risk when considering approaches to family planning. By the time Margaret Sanger and other activists began campaigning for legal contraception in the 1910s, Americans had been effectively controlling fertility for a century, combining old techniques with explosive new ideas. Birth Control and American Modernity charts those ideas, capturing a movement that relied less on traditional public advocacy than dispersed action of the kind that nullified Prohibition. Acting in bedrooms and gossip corners where formal power was weak and moral feeling strong, Americans of both sexes gradually normalized birth control in private, then in public, as part of a wider prioritization of present material worlds over imagined eternal continuums. The moral edifice they constructed, and similar citizen movements around the world, remains tenuously intact.