The sketch of the School of Athens of Raphaël at the Pinacoteca Ambrosiana of Milan, seized by the French in Paris in 1797 is considered to be in an alarming state of conservation. It is the object of a controversy having a bearing on the legitimacy of a new relining and on the possible retouches to be given to the work. For the first time, the principle has been more clearly expressed for not reconstituting the missing parts of the drawing. It seems it is also the first time that a debate on the principles of conservation and restoration of graphic works is taking place in public and that those responsible are justifying the principles and the methods used. Studies of the printed texts and the archive documents enable specifying these points that had never been more completely used in the context of history of conservation.