The book with almost 200 sources from the prehistory and early period of the Reformation represents a complete revision of the work published by Karl Kaulfuss-Diesch in 1917: "The Book of the Reformation" as well as other new editions. The earlier selection of sources was subjected to a critical revision, supplemented and partially expanded. All texts are explained by a brief introductory text and provided with further references. The result is a kaleidoscope of various approaches to the ecclesiastical and political reform demands of the late Middle Ages and their concentrated intensification in the programmatic statements of the German-speaking, especially Lutheran, Reformation. At the same time, by including older sources, the volume provides a preliminary overview of the lasting impact of the evidence of reformatory initiatives and the contradiction they provoked.