What has made the Mona Lisa the most famous picture in the world? Why is it that, of all the 6,000 paintings in the Louvre, it is the only one to be exhibited in a special box, set in concrete and protected by two sheets of bulletproof glass? Why do thousands of visitors throng to see it every day, ignoring the masterpieces which surround it? For nearly 500 years the painting - and the mysterious smile on the face of the sitter - has been a source of mystery, speculation and reverence. In this book Donald Sassoon describes not only the Mona Lisa and its history, but its mythology, and the processes which combined to raise it to its current unrivalled level of fame. He examines Leonardo's innovative techniques; the problems concerning the identity of the sitter; what happened after to the painting after it left Italy when Leonardo joined King Francois I's court in France; the copies made in the 17th century; its celebration by 19th-century intellectuals; and its theft. A narrative history of how Leonardo da Vinci's painting of the Mona Lisa came to be the most famous in the world - and one of the most powerful cultural icons of our time.