The extra-liturgical prayers in honour of Mary most frequently illustrated in fifteenth-century French and Flemish Books of Hours are the Obsecro te, O intemerata and “The Fifteen Joys of the Virgin”. The presentation of a religious image on the page opposite the patron at prayer resembles the devotional panel diptych common in fifteenth-century Flanders. In the late fifteenth-century Hours of Joanna of Castile, the beginning of the prayer to the Virgin is faced by a full-page Virgo lactans within a narrow frame. The expressions, postures and gestures of the devotional group freely communicate the means of salvation through the Virgin’s role in the Incarnation and Christ’s redemptive sacrifice. The intrusion of the portrait could be moderated by manipulating colour and degrees of compositional clarity, or by locating the portrait within a different focal range from the devotional group.