In the XVIth century, Thessaloniki experienced the health problems of a large international metropolis. With Byzantine medicine surviving only in the nearby monastic centre of Mount Athos, the city found it easy to accept the medical practice introduced by the Sephardic Jews, newly arrived from Iberia. Excelling among the newcomers was Amatus Lusitanus, who wrote his major work Curationum Medicinalium Centuriae Septem in Thessaloniki. In the town's multicultural ambience, the Hippocratic Oath was universally acknowledged as the basis of medical ethics, with various traditions providing their own interpretations. In the framework of Byzantine science, this respected text had been interpreted from a Christian viewpoint, while on their side the Ottomans recognised the numerous Islamic efforts to regulate the conduct of doctors. The Sephardic community added their own thoughts, some old, some new, while Western Europe adopted standards for the specific needs of schools of medicine. The Oath of Amatus, published in 1561, was a product both of the varied medical traditions of Antiquity and of the Middle Ages. It owed much to the special conditions existing in Thessaloniki, where a new scientific perspective was added to the ethical foundations of medicine.