“Prizeworthy Research?” Wilhelm Roux and His Program of Developmental Mechanics. The Nobel Prize in physiology or medicine is awarded annually to a maximum of three laureates. Not surprisingly, the number of nominees is much larger. Drawing on Nobel Prize nominations in the Nobel archives in Sweden, the core of this paper deals with the nomination letters for the physiologist Wilhelm Roux to discuss competition and some controversies among German physiologists around 1900 in this particular context. The paper elucidates the arguments (...) brought forward to portray Roux as a scientist who had conferred “the greatest benefit to mankind” in the field of physiology or medicine ; examines some other runners-up, and reconstructs why Roux as well as some of his peers were not awarded the Nobel Prize. On a more general level, we argue that an analysis of Nobel Prize nominations contributes to a broader history of excellence in science and medicine in the twentieth century. (shrink)