His piece “Sentences on Conceptual Art” is published in issue 5 of 0 to 9 magazine; it becomes one of the most widely cited artists' writings of the 1960s, exploring the relationship between art, practice and art criticism.
1966
“Primary Structures” at the Jewish Museum
Takes part in the “Primary Structures” exhibition at the Jewish Museum in New York, a seminal show that helped define Minimalism, submitting an untitled open modular cube of nine units.
1968
A drawing for the opening of the Paula Cooper Gallery
He creates a work for the inaugural show of the Paula Cooper Gallery, an exhibition to benefit the Student Mobilization Committee to End the War in Vietnam; since then thousands of his drawings have been installed directly on walls.
27 juni 1968 – 6 oktober 1968
Exhibition: 4. documenta
1969
“When Attitude Becomes Form” in Bern
Harald Szeemann invites him to take part in “When Attitude Becomes Form” at the Kunsthalle Bern, Switzerland.
1970
First retrospective in The Hague
The Gemeentemuseum in The Hague presents his first retrospective exhibition.
