He was known worldwide as a soloist with major orchestras, a recitalist on four continents, a recording artist, and for his master classes, visiting professorships, and the Swiss music festival he organized in Ernen.

Encouraged by his cellist friend János Starker, at the age of forty, he went to Indiana University School of Music in Bloomington, starting what is considered to be the most productive phase of his career.

Sebők was a guest professor of the Berlin Hochschule der Kunste (HDK) in Germany, there teaching master classes twice a year.

In 1973 he founded and organized annual summer master classes in Ernen, Switzerland for pianists and 'other instruments', and the following year he was a member the jury for the first Paloma O'Shea Santander International Piano Competition.

[2] He also founded and directed the "Festival der Zukunft" in Ernen in 1987, which is to this day carrying his legacy with growing numbers of concertgoers.