The modally organized collections of the 16th century invite considering the role of modality. Bernhard Meier and Harold Powers provide two diverging points of view on this question: for Meier, modality is an essential feature of Renaissance music, while for Powers the modal organization is but a superficial character. The present paper examines the Livre de chansons nouvelles from these two points of view. Applying Meier's theory, it browses through the ambitus, the melodic contour, the species of intervals and the cadences of each of the pieces; the question of the ethos is also briefly considered. The pieces are then classified in "tonal types" according to Powers' theory. It appears that Meier's criteria do not always allow identifying the mode. That the three last pieces are not modally arranged leads to consider that the organization of the collection was done a posteriori.