These pilgrims are no ordinary Muslims, though; they belong to a movement called Tablighi Jamaat ("Proselytizing Group"). They are trained missionaries who have dedicated much of their lives to spreading Islam across the globe. The largest group of religious proselytizers of any faith, they are part of the reason for the explosive growth of Islamic religious fervor and conversion.
Despite its size, worldwide presence, and tremendous importance, Tablighi Jamaat remains largely unknown outside the Muslim community, even to many scholars of Islam. This is no coincidence. Tablighi Jamaat officials work to remain outside of both media and governmental notice. Tablighi Jamaat neither has formal organizational structure nor does it publish details about the scope of its activities, its membership, or its finances.