This interdisciplinary book integrates the historical practices regarding material excrement and its symbolic representation, with special focus on fecopoetics and Chaucer's literary agenda. Filth in all its manifestations - material (including privies, dung on fields, and as alchemical ingredient), symbolic (sin, misogynist slander, and theological wrestling with the problem of filth in sacred contexts) and linguistic (a semantic range including dirt and dung) - helps us to see how excrement is vital to understanding the Middle Ages. Applying fecal theories to late medieval culture, Morrison concludes by proposing Waste Studies as a new field of ethical and moral criticism for literary scholars.