This article deals with the Papal Mission Project in the Diocese of Łomża during the Second Polish Republic. The project was a joint effort of three organizations, the Papal Project of the Propagation of the Faith, the Papal Project of Missionary Childhood, and the Missionary Union of the Clergy. They had a membership of a few thousand (eg. in 1938 it reached 12,430). They owed their impressive development to the active support of Bishop Łukomski, who regarded commitment for the missions an important element of the priesthood. The expansion of local branches and rise in membership resulted in increased and more diverse activity. The primary aim of the Papal Mission Project was to awaken and form in each believer of a worldwide mission awareness, based on Gospel charity and expressed through prayer, self-denial and sharing. It should be added that these associations not only assisted their members in shaping their inner lives but also tried to exert an influence on the whole social milieu in which they worked.