The amount of international conferences that were organised over the nineteenth century increased rapidly, and formed an ideal environment for discussions amongst peers and establishing knowledge transfers. Medical and psychiatric conferences were no exception. However, a study into psychiatric conferences on a larger scale has not yet been conducted. Adopting a transnational perspective is essential, and while this approach is gaining more attention from historians more generally, it is only slowly reaching the history of psychiatry. To gain insights into the (inter)national knowledge dissemination that happened within psychiatry, we will examine different organisational aspects such as the locations where conferences were held, its organisation and the subjects and questions that were included in the conference program, as well as studying the mutual connections between congresses and the connections between the participants. This will help to discover the key players and whether it was well-known psychiatrists that were most involved in these international conferences. These interwoven sub-questions will help to establish in how far an international community existed within psychiatry and thus if such international congresses were an epicentre of transnational knowledge dissemination or if they were rather a manifestation of national encounters. This research is based on the minutes and membership lists found within conference proceedings of the “Congrès internationale médecine mentale”, “Congrès international de neurologie, psychiatrie et de physiologie”, “Congrès international de l’assistance aux aliéné” and the “Congrès international de médecine” that also often included a section dedicated to psychiatry. These all took place between the 1860’s and the first decade of the twentieth century.