Given her background in education, Auger was a natural vocal teacher. Auger left the State Opera in 1974 to pursue her burgeoning concert career and to devote more time to teaching at the Salzburg Mozarteum, where she held a full professorship for a time in the early 70s. Among her pupils was soprano Renée Fleming, who studied with her in Germany during her year there as a Fulbright scholar. In the mid 70s, she traveled to Japan with Helmuth Rilling, serving at the last minute as a soloist in Bach's "St. Matthew" Passion. (She learned the part on the plane.) It was the beginning of a long and fruitful association with the German conductor, one that has yielded over 40 recordings. Her debut at La Scala was in 1975 in "L'enfant et les sortilèges". From this time, she turned to lyrical roles in opera, preferring to focus on her career as a concert singer, in early music as well as lieder, often accompanied in the latter by pianist Irwin Gage. She performed most of the soprano parts in Helmuth Rilling's Bach cantata cycle of the mid-1970s to mid-1980s, appearing several times at Rilling's Oregon Bach Festival. At the other end of the spectrum, she commissioned new song cycles by Libby Larsen ("Sonnets from the Portuguese") and Judith Lang Zaimont. Her association with Rilling led to Auger's first break in the United States, in 1980, when Blanche Moyse, the director of the New England Bach Festival, heard her sing with Rilling at the Oregon Bach Festival and signed her for a series of concerts the following season.