The most important work of the Order is fulfillment of its mission of glorification of the Cross, practiced by the celebration of regular Masses in the various churches supported by the Order and commemoration of the Order’s principal feast days. The Order is also engaged through its National associations or commissions in several different activities, to which all members are expected to contribute to the extent they are able. The members are also urged to promote the propaganda of the Faith and defence of the Holy Roman Church, through their public activities and private example.

These are firstly support of the Basilica of Santa Croce al Flaminio and its parochial mission. This Church was constructed by the Holy See in the neo-Byzantine style and houses the Chapel of Saint George, dedicated by His Holiness Pope Benedict XV. Construction of this chapel was paid for by members of the Order (whose names are commemorated in a plaque on the wall), among whom was Monsignor Eugenio Pacelli, later Pope Pius XII.

Secondly, support of the Hospital de la Sainte Famille (Hospital of the Holy Family), Bethlehem, the largest maternity hospital serving the Palestinian Arab community and based in the very town where Our Lord Jesus Christ was born. The Holy Father has declared this hospital one of the 100 most important humanitarian enterprises of the Church during this year of Charity, 1999 and also a special object of support for the Millennial year. The American Committee for the Holy Family Hospital, whose four members are all Knights of the Order, has raised more than $350,000 for this hospital since 1995.

The Order has also contributed to relief appeals for refugees in Bosnia, and made a substantial donation to the fund for reconstruction of the Basilica of Saint Francis at Assisi. Earlier in 1999 His Royal Highness the Grand Master was pleased to make a direct donation in the name of the Order to the Holy Father for his charitable works, through the Apostolic Nuncio in Madrid.

In 2002, thanks to the generosity of a Brazilian member, the Order contributed hearing aids to the Pontifical Institute Ephpheta Paul VI, for Audio-Phonetic Rehabilitation in Bethlehem; to the Brazilian Setentrional Association of the S. M. O. M., and to the Centro Asistencia of the Brazilian Meridional Association of the S.M.O.M.