In the second half of the fourteenth century there are many instances of well-established Sienese master-painters collaborating on single commissions. It may be that the development was precipitated by the fact that there was not much work to go round and it had to be shared among different painters. But it seems more likely that the reverse was the case and that too much was being demanded of fewer specialist craftworkers. This large altarpiece signed on its lower edge by both Niccolò di Ser Sozzo and Luca di Tommè in 1362 provides a striking example of such collaboration. Now divested of its original piers, pinnacle panels and predella, the altarpiece was painted probably for the high altar of San Tommaso, a church under the care of the religious order known as the Humiliati. Accordingly, the apostle Thomas is portrayed on the Virgin's right-hand side, a position conventionally understood as that of greatest honour. To his right appears Saint John the Baptist, while Saints Benedict and Stephen appear to the left of the Virgin. The general consensus among art historians is that Niccolò di Ser Sozzo painted the Virgin and Christ Child, Saint Benedict and Saint Stephen while Luca di Tommè painted Saints John the Baptist and Thomas.