Setting the stage for the special forum, this introduction points to the centrality of science diplomacy activities within many current foreign policy concepts around the world. It also points to the lack of historical perspective within many current academic debates about science diplomacy. Suggesting the value of such a perspective, the introduction then draws attention to a number of fruitful contributions that histories of science diplomacy may make to contemporary history. These include: a better understanding of how entanglements between science, foreign policy, and international relations evolved over the twentieth century; a refined understanding of the workings of foreign relations and diplomacy that sheds light on the role of science as an arena of foreign relations; new insights into the Cold War; a globalizing of perspectives in the writing of contemporary history; a new international focus on widely under-researched actors like universities, science movements, science organizations, and science academies; a focus on new themes that range from global environmental problems to issues like cultural heritage. The remainder of the introduction then delineates some of the shared assumptions and findings of the essays and then briefly introduces each contribution to the special section.