This book, was made possible thanks to a collaboration with the Yves Klein Archives. For the first time ever a book shows through various images the story of the relationship between Yves Klein (1928-1962) and the USA : fascination, mutual influence, successful or missed encounters, exchanges, travels… Many documents, often unpublished before, demonstrate through photographs or letters, four important steps (Paris, New York, Los Angeles, Paris) during which Klein forged links with the United States. Flipping through those pages, many important figures of the American artistic scene are evoked: Leo Castelli, Robert Rauschenberg, Jasper Johns, Marcel Duchamp, Virginia Dwan, Ed Kienholz… This exceptional album opens with an interview with Rotraut Klein-Moquay who shares her memories of her trip with Yves Klein to the United States in 1961, followed by a chronology of Yves Klein’s work. It also presents an original essay by the American art historian Robert Pincus-Witten, who met personally the protagonists of this adventure. This book, essential in the 20th century art history, also holds several unseen documents in their entirety such as the Chelsea Hotel Manifesto.