He began the first collection of American contemporary art at the Stedelijk. Under his direction, in 1971, debates about the museum's social and educational functions sparked the formation of a communications department.[11] In the early 1970s, the museum made its first acquisitions of video art by European artists including Dibbets and Gilbert & George. Today, the collection of video art contains around 900 works and installations, including works by Nam June Paik, Bill Viola and Bruce Nauman.