Zygmunt Mycielski (1907–1987), a composer and writer on music, was one of the pupils of Nadia Boulanger (1887–1979). In his writings he often stressed the role which this eminent French teacher played in the development of a whole generation of Polish (and not only Polish) composers. Not only did Mycielski owe a lot to her personally, but he also clearly saw the significance of her teaching to the further fate of Polish music. He remained her friend, introduced her to Poland, and often mentioned both his education under her wings and the importance of her teaching. The article presents the figure and role of Nadia Boulanger in the light of the writings of Zygmunt Mycielski.