His research centres on the transmission of texts, techniques and artefacts from the Arab world to the West, especially in the Middle Ages. He has documented this transmission by editing and translating several texts that were first translated from Arabic into Latin, and also by describing the historical and cultural context of these translations. Throughout his research and his publications he has aimed to document the extent to which Arabic authorities and texted translated from Arabic have shaped European learning, in the universities, in medical schools and in esoteric circles. Among his books in this subject area are The Introduction of Arabic Learning into England (1997), Arabic into Latin in the Middle Ages: The Translators and their Intellectual and Social Context (2009) and Numerals and Arithmetic in the Middle Ages (2010). Other interests include Jesuit education in Japan in the late sixteenth century, the use of Japanese themes in Latin drama in Europe in the seventeenth century and the use of music in therapy and in the Christian mission.