Ellsworth Kelly belongs among the most important exponents of international post-war art. With abstract expressionism at its peak the American artist developed a painterly vocabulary that leaves traditional panel painting behind. In a conscious questioning of the conditions that underlie our perceptions, he not only explores the relationships of picture and wall, sculpture and space but also, and in particular, the relationship between viewer and work. Based on a store of about 40 works, primarily in the possession of the artist, this book is an investigation into Ellsworth Kelly's artistic development that spans five decades.