On March 3, 1863, Senator Henry Wilson of Massachusetts rose in the Senate chamber to, as he told his colleagues, "take up a bill...to incorporate the National Academy of Sciences." He read two short paragraphs concerning membership and the obligation of the Academy to " whenever called upon by any department of the Government, investigate, examine, experiment, and report upon any subject of science or art." The Senate passed the bill by voice vote, and a few hours later, the House passed it without comment. Later that evening, President Abraham Lincoln signed the bill into law. In the century and a half since 1863, the National Academy of Sciences (NAS) has grown from a small band of 50 charter members - each of whom was specified in the founding legislation - to an organization of more than 2,500 national members and foreign associates. In 1916, the Academy created the National Research Council, which today recruits thousands of specialists each year from the scientific and technological communities to participate in the Academy's advisory work. The establishment of the National Academy of Engineering in 1964 and the Institute of Medicine in 1970 resulted in a multifaceted institution that investigates issues ranging widely across the sciences, technology, and health. The charter members of the Academy, who met for the first time on April 22, 1863, in the chapel at New York University, scarcely could have envisioned what their fledgling organization would become. To celebrate the Academy's sesquicentennial, the Arthur M. Sackler Colloquia of the National Academy of Sciences, with additional support from the W. M. Keck Foundation, the Ford Foundation, and the Richard Lounsbery Foundation, held a meeting in Washington, DC, on October 16-18, 2013, entitled "The National Academy of Sciences at 150: Celebrating Service to the Nation." The meeting began the evening of October 16 with the 2013 Annual Sackler Lecture by Daniel J. Kevles, Stanley Woodward Professor of History, History of Medicine, and American Studies at Yale University, who reviewed the first century of the Academy's history in the context of its dual mission to advance science and serve the government. Over the next 2 days, eight groups of speakers examined topics where the Academy's advice has been especially consequential. On the first day, which was focused on science, politics, and policy, the speakers discussed national security and international relations, the International Geophysical Year and the space sciences, climate change, and biology in public policy. On the second day, which examined the nation' s infrastructure in health, information, and education, the topics addressed were radiation hazards, biodemography and vital statistics, computing and information, and K-12 science education. This supplement to the Proceedings of the National Academy of Sciences contains the edited spoken remarks of the presenters along with short introductions to each of the eight areas discussed. Free downloads of many of the reports mentioned by the speakers are available at www.nap. edu, and Webcasts of the colloquium are available on YouTube.*.
