A pioneer is a volunteer, a Bahá’í, who leaves his or her home to journey to a different geographical location (home country or foreign) for the purpose of teaching the Bahá’í Faith and assist in establishing and/or consolidating Bahá’í communities. The act of moving to a new location is termed pioneering. Bahá’ís refrain from using the term “missionary”, closely associated with the Christian religion. The first Bahá’í pioneer to enter a country or region mentioned in `Abdu’l-Bahá’s Tablets of the Divine Plan is given the title of Knight of Bahá’u’lláh.
During the Ten Year Crusade, which ran from 1953 to 1963, hundreds of pioneers settled in countries and territories throughout the world. This eventually led to the establishment of 44 new National and Regional Spiritual Assemblies (Bahá’í administrative bodies) and increased the population of Bahá’ís’ worldwide.