As of June 2, 2011, all PDF versions of books published by the National Academies Press (NAP) are downloadable free of charge to anyone. This includes the current catalog of more than 4,000 books plus future reports published by NAP.
Free access to online content supports the mission of NAP to improve government decision-making and public policy, increase public education and understanding, and promote the acquisition and dissemination of knowledge in matters involving science, engineering, technology, and health. Like no other organization, the National Academies can enlist the nation’s foremost scientists, engineers, health professionals, and other experts to address the scientific and technical aspects of society’s most pressing problems through the authoritative and independent reports published by NAP.