This article discusses the history of the so-called “book program”—a joint effort by the U.S. government, the East European diaspora, and readers of prohibited books behind the Iron Curtain. Between 1956 and 1989 the program purchased some 10 million copies of publications and delivered them to people in Soviet–dominated Eastern Europe in order to undermine communist rule. Using the historical materials of the Polonia Book Fund, a U.S.–sponsored publishing project for Poland, this article contributes new insights on the transatlantic perspective of the cultural Cold War. This article focuses on the program’s early stages, and describes various elements of the transnational smuggling network. The program’s state-private partnership was a workable solution that helped to foster a diversity of opinions in post-Stalinist Poland.