When historians turn to the social sciences for help with the task of ordering their data or making their sources speak more clearly, the results can be rewarding in unexpected ways. So it is if one applies the twin concepts profession and professionalization to the German context-in particular, to the history of German engineers in the nineteenth century. At first sight, an idea like the “professionalization of the German engineers” seems straightforward enough. In tandem with the growth of Germany's science-based industries and unparalleled system of technical education, it suggests the emergence of the men who occupied the critical positions in these institutions and embodied technological progress. A notion such as the “rise of the German engineering profession,” therefore, stirs visions of a grand metamorphosis, in which the land of poets and thinkers—and of Junkers, bureaucrats, and mandarins—turned into the world of Siemens, Porsche, Mannesmann, Bosch, Diesel, Daimler-Benz, etc.