A central figure in the California Light and Space movement, Robert Irwin (b. 1928) has been creating installations and works of art for over six decades that challenge viewers’ perceptions of the world around them. Irwin’s “site-conditioned” projects take their cues from, and are dependent on, their surroundings, resulting in unexpected visual and aesthetic outcomes. Robert Irwin: Scrim veil—Black rectangle—Natural light, Whitney Museum of American Art, New York (1977), made specifically for the Whitney’s fourth floor gallery, is a work that Irwin has described as setting the course for his subsequent career. On the occasion of its reinstallation, Irwin considers the importance of his long-standing interest in creating site-conditioned projects. He speaks about this seminal example and its significance for his larger career in conversation with Donna De Salvo, the Whitney’s Chief Curator and Deputy Director for Programs.