The Society for the Propagation of the Faith is one of the four Pontifical Mission Societies. It seeks prayer, sacrifice, and financial support from high school and college students and adults, which helps to provide support for pastoral and evangelizing programs of mission dioceses around the world.

The General Fund of the Propagation of the Faith, which gathers gifts from Catholics all over the world, is the basic means of support for the Catholic Church's worldwide missions. In the United States, money for this fund is collected in a variety of ways, including World Mission Sunday (a day set aside primarily to encourage prayers and financial help for the missions from all Catholics during the month of October, which is World Mission Month), MISSION Magazine, direct-mail appeals, parish appeals, planned giving programs, wills, estates, and trusts.

Offerings received by the Propagation of the Faith in the United States are joined with offerings from all other countries and are distributed annually to more than 1,100 mission dioceses and vicariates around the world. The Propagation of the Faith is established in every country where the church is free to operate.