On this fortieth anniversary of Marialis Cultus, we wish to commemorate Paul VI and Ignacio Calabuig, both of whom made singular contributions to implementing Vatican II’s directives for the reform and strengthening of Marian devotion in the liturgy, or, as expressed at Vatican II, who collaborated “that devotion to the Virgin Mary, especially in the liturgy, be generously fostered” (LG 67). Here a brief introduction presents Paul VI and Ignacio Calabuig and their views on Marian devotion and liturgy; a description of the causes for the postconciliar Marian crisis follows. Their collaborative response is found in Paul VI’s 1974 Apostolic Exhortation Marialis Cultus (MC), which dealt with the Virgin Mary in the postconciliar revised texts of the Roman rite and with the reform of Marian devotions (including the rosary). Paul VI presented the Virgin as Mother and Exemplar of the Church. Later, Calabuig continued the integration of Marian devotion into the liturgy through the Collection of Masses of the Blessed Virgin Mary (1986), in his directives for the observance of the Marian Year (1987), and in various documents for the Servite community.