The classic formulation of medical traditions in ancient Greece seems uniquely suited for mapping the world of the extraordinarily diverse Muslim societies. This chapter outlines an approach to the analysis of these medical systems. Presenting a comparative study of Greco-Islamic medicine, it describes the symbolic dimensions of Greco-Islamic medicine (the counterpart to Ayurveda and classical Chinese medicine) concentrating on ethnographic rather than historical aspects of its integration into local Muslim cultures. It discusses some aspects of the symbolic organization of Islamic medicine, which seem particularly important for analyzing how Greco-Islamic medicine is integrated into local cultures and for comparing forms of medicine in diverse Islamic societies. It also discusses the cultural authority of Islamic medicine and biology, using a perspective as a vantage to explore their relation to codes of power, sexuality, and the sacred and to consider medical revivalism.