Hundreds of thousands of conferences have taken place since their first appearance in the late eighteenth century, yet the history of science has often treated them as stages for scientific practice, not as the play itself. Drawing on recent work in the history of science and of international relations, the introduction to this special issue suggests avenues for exploring the phenomenon of the international scientific conference, broadly construed, by highlighting the connected dimensions of communication, sociability and international relations. It lays (...) out a typology of scientific conferences as a way of gaining an overview of their diversity in the nineteenth and twentieth centuries. It argues that the international scientific conference is a central locus for understanding science as a social, cultural and political practice. (shrink)