Books are the most important medium of communication in the humanities, a major medium in the social sciences, and a central component of academic library collections. This study examined humanities and social sciences books that won prizes from ten leading United States disciplinary associations between 2000 and 2009. The study extends earlier research for the 1990s. It reports substantial interest by most disciplines in books about subjects classified in other disciplines; dominance of university presses over commercial publishers in prizes won; and, between 2012 and 2014, great growth in library holdings of electronic versions of prizewinners.