1953

Professor at the Royal Academy of Fine Arts of Antwerp, Belgium.

1961

Professor at the University of British Colombia, Vancouver, Canada.
Professor at the National Institute of Fine Arts, Antwerp, Belgium.

1968

Professor at the University of Iowa, USA.

1969

Lectures at the Universities of Wisconsin, Colorado and Drake (Des Moines), USA.
Lecture at the Art School of the Modern Art Museum of Atlanta, USA.

1977

Seminar in the United States, at the University of Colorado (Boulder), and in the Art Schools of Minneapolis, Atlanta and Philadelphia, USA.

1984-87

Lamar Dodd Chair for sculpture at the University of Georgia, USA.