When the picture is begun the age of Mona Lisa is 24 years, that of Léonard 51 years. It is in Florence that the picture was carried out. It puts in scene an young woman, represented with half-length, in a loggia. Dressed with a great simplicity, it adopts an installation of three quarters, directs its glance towards the spectator and outlines a light smile. Its silhouette is detached on a bottom from misty landscape, carried out with a great meticulousness, with the background its character is unreal, in the foreground one perceives rocks, a sinuous road and a small bridge. The place occupied by the landscape is unusual for the time it shows the great independence of mind and the capacity of innovation of the painter. Modelled is equipped with a softness and a great subtlety. This effect is reinforced by the sfumato, returned of a vaporous atmosphere characteristic of the manner of Léonard who associates bottom and form and makes almost immaterial contours. The work, carried out using a very reduced pallet, testifies to one great depth psychological. Wrapped by this diffuse light, Mona Lisa, mysterious and attractive, seems an ideal figure. Exceeding the stage of the simple portrait, work is affirmed like a synthesis of a great complexity of the searchs of Leonardo da Vinci and its perception of nature and Universe. It is also one of the highest expressions of its Article.Leonardo da Vinci will never separate from work, taking it along as far as France where it is acquired by François 1st, it is preserved at the Museum of the Louvre in Paris.