From Sotheby's auction house:
Painted in 1965, Buste de femme illustrates Picasso’s ongoing exploration of the female form. Picasso met Jacqueline Roque in 1952 at the pottery studio in Vallauris, when he was still living with Françoise Gilot. The artist soon fell under her spell and, following his separation from Gilot in 1954, Jacqueline became his principle model and muse; his depictions of her constitute the largest group of images of any of the women in his life.
In the 1950s Jacqueline served as a model for several of Picasso's reinterpretations of art historical masterworks, including his studies of Manet's Déjeuner sur l'herbe and Delacroix's Femmes d'Algers, but from the early 1960s Picasso was increasingly interested in making her the singular focus of his attention. He experimented ceaselessly with different modes of representing her; she is depicted as one half of a kissing couple or an artist and model, and as the sole subject of paintings. In some of these works she is shown as a reclining nude and in others Picasso focuses on her upper torso and face; she is captured in profile, facing out at the viewer, in languid repose or with her body dramatically foreshortened. These endless variations are matched by Picasso’s technical virtuosity – sometimes her features are abstracted to a handful of lines and at other times – as in the present work – she is rendered with a deliberately unstudied naturalism.