Originally published in conjunction with Robert Irwin’s 1977 retrospective at the Whitney, this exhibition catalogue has been digitized to coincide with the reinstallation of Scrim veil—Black rectangle—Natural light, Whitney Museum of American Art (1977) on the fourth floor of the Museum. Created in close collaboration with the artist at the time of the original exhibition, this book contains Irwin’s seminal essay “Notes Toward a Model” in which he puts forth his thinking about aesthetics, perception, conception, experience, and the idea of compounded abstraction. It also includes documentation of and plans for some of the artist’s other projects as well as a short chronology and selected exhibition history and bibliography. A new introduction by Donna De Salvo, Chief Curator and Deputy Director for Programs, offers insight into how and why Irwin’s work continues to resonate today.