The Roman memorial altar devoted to Stanislaus Kostka (1550–1568), a Polish saint of international importance, was an exceptional example of how a modern reredos was constructed in the era of the counterreformation. Located in the Jesuit novitiate, the Church of Sant’Andrea al Quirinale is part of an unusual facility for the veneration of Kostka, which focuses on two separate entities – the chapel of the novitiate church and the monastic cell. The paper attempts to determine the role of the altar (which has undergone modifications and exhibits Kostka’s effigy) as the most significant object of worship and liturgy. Three phases can be distinguished:1) the first reredos, resembling an altar over the saint’s grave, was constructed in about 160...