One of the most extraordinary musical personalities of the twentieth century, a teacher of several generations of European and American composers. She taught Mycielski from the very beginning of his time at Paris’ Ėcole Normale de Musique – beginning with theoretical subjects and then moving to composition. He admired her erudition as well as remarkable industriousness and devotion to her students. She quickly became his guide in the world of music and culture, and with time also his close friend. He often wrote about her teaching and took care of her during her visits to Poland. He highly valued her involvement in the education of Polish composers and clearly saw her role in the development of Polish music. Remembering the lessons she gave in her own flat, he wrote:

Several generations from several continents came here to listen, think and love music. (Z. Mycielski, „Nadia Boulanger", in: „Szkice i wspomnienia"  [Sketches and Memoirs], Warsaw 1999). 

He himself remained one of her closest students and friends.