In the history of science in general and the history of medicine in particular, translation played an crucial role. It often was through the contact with other cultures that scientific and medical ideas developed. The present symposium focusses on the transmission of medical ideas, and breaks new ground in that it challenges the facile idea that medicine was transmitted from Greek into Arabic and hence into Latin. In fact, a multiplicity of encounters took place that included Ancient Egyptian and Indian material. Furthermore, the concrete examples of Ḥunayn ibn Isḥāq, ʾAbū Bakr Muḥammad ibn Zakariyāʾ al-Rāzī, and Qusṭā ibn Lūqā demonstrate that Arabic-speaking physicians in the Abbasid Empire did not merely transmit previous knowledge, but in fact engaged with it critically. This critical engagement is also visible in the many Arabic commentaries on the Hippocratic Aphorisms, thus showing that commentaries often constituted venues for innovation and change. One can perhaps even perceive here certain aspects of evidence-based medicine. Finally, European university medicine drew heavily on the Arabic medical tradition, and vice versa, as examples from the Ottoman period illustrate.