From FSSP website:   The Priestly Fraternity of St. Peter (FSSP) is a clerical Society of Apostolic Life of Pontifical Right, canonically erected by Pope St. John Paul II in 1988. Their priests serve in apostolates across the world, with the faithful celebration of the traditional Mass and Sacraments (Extraordinary Form of the Roman Rite) at the center of their charism. The members of the Priestly Fraternity of St. Peter, nourished through the spiritual riches of the Church’s ancient Roman Liturgy, strive to sanctify the seminarians, religious and faithful entrusted to their pastoral care.

The Fraternity has chosen St. Peter as their special patron in order to express their gratitude, filial love, and loyalty to the Supreme Pontiff. With more than 300 priests and 150 seminarians from 30 countries, the Fraternity serves in over 130 dioceses on 5 continents. International headquarters are located in Fribourg, Switzerland and North American headquarters in the Diocese of Scranton, Pennsylvania. Fraternity seminarians receive training at one of two international seminaries: Priesterseminar Sankt Petrus in Wigratzbad, Germany (for German and French speakers) and Our Lady of Guadalupe Seminary in Denton, Nebraska (for English speakers).

Using the ancient liturgy as our well-spring, we form our priests in the traditions of the Church to serve at the altar and in the parish so that the fullness of Christ might enter the emptiness of the world.