Is it painting or sculpture? This literally outstanding exhibition catalog deepens our understanding of a genre-bending medium over the course of nearly two centuries. No other artistic medium transcends the boundaries of our vision quite like the relief; this very ambiguity has tempted some of the world's greatest artists to explore its possibilities. Delving into the subject of reliefs in modern art, this book presents to readers the unique opportunity to do some exploring themselves. From 1800 on, it traces the relief's fluid aesthetic, and illuminates the significance of innovation and adaptation until the 1960s. Opening with neoclassical works that echoed the reliefs of ancient Egypt, Greece and Rome, the authors examine sculptors who deliberately defied the boundaries of their medium, such as Jules Dalou, Auguste Rodin, and Medardo Rosso, juxtaposing these works with those of painter-sculptors such as Edgar Degas, Paul Gauguin, and Pablo Picasso. Readers will learn how Dadaists such as Kurt Schwitters, Hans Arp, and Sophie Taeuber-Arp transformed the techniques of collage and assemblage using found materials, and how Henry Moore, Louise Nevelson or Lee Bontecou ushered in a return to monumental, large-scale works. Filled with highest quality reproductions and photographs, this book celebrates the evolution of a means of creative expression that started as a dialectic between genres and which, over decades, has achieved the status of an artistic medium in its own right.