This biographic entry explores the international trajectory of Josef Brožek and his role in the development of the history of psychology as a field of research. From the 1960s onward, Brožek engaged in multiple academic exchanges, research collaborations, and institutional efforts across different countries and universities. His involvement included participation in congresses, archival research, the establishment of journals, reflections on the history of psychology, and support for the creation of working groups and collaborative projects. Notably, he contributed to the formation of scholarly networks in countries such as Italy, Germany, Spain, and Brazil. In the latter case, he collaborated with researchers through lectures, guidance, and by supporting the development of academic programs and archives. His work highlights the importance of international dialogue, the circulation of knowledge, and the integration of different historiographical and psychological traditions. Based on documents and publications, this account shows how Brožek’s transnational activities contributed to the consolidation of the history of psychology as a field of research.