The Tacuinum sanitatis is a genre of illuminated medical texts from the Late Middle Ages that contains an intriguing and surprising combination of theoretical knowledge and lavish, detailed, and colorful images. By exploring a specific manuscript of this genre, and by comparing it with related practical medical texts and genres, this study wishes to better understand the different aspects of this text and explain this combination. The Late Middle Ages are traditionally thought of as a time of stagnation in the history of science and particularly in the history of medicine. However, in recent decades historians have observed the long-term intellectual and social evolutions of the Middle Ages and have demonstrated the ways in which these changes formed the grounds for the great achievements of the sixteenth century. These evolutions include the translations and dissemination of Greek and Arab knowledge traditions in the Latin West, the establishment of universities, the formation of a medical market and the medicalization of society, and the formation of new audiences for practical and theoretical medical texts. The arts were also heavily influenced by the rise of naturalism and natural study from direct observation, for example. This study demonstrates how a singular text can be linked to major historical evolutions and how a text of this sort can function as a historical source, shedding light on the major intellectual and artistic shift between the Middle Ages and the Renaissance.