At age 27, he was named Associate Conductor of the Amsterdam Concertgebouw Orchestra, a post he held for five years.
He continued to assist Fricsay both in Salzburg and in Berlin with the RIAS Symphony Orchestra and Deutsche Grammophon through 1964.
In 1965, Erős came to the United States for the first time at the invitation of George Szell to work with him and the Cleveland Orchestra as a Kulas Foundation Fellow.
Erős came to the University of Washington School of Music in Seattle, Washington in 1989 as the Morrison Endowed Professor of Conducting and Music Director and Conductor of the University Symphony and Opera, where he taught until his retirement in 2010; up until his death, he held the honorary title of Professor Emeritus.
[6] He also conducted the first recording of the opera Jesus Before Herod by Hungarian composer Gabriel von Wayditch (1888–1969)[7] with the San Diego Symphony.