ummary: The mission of the Church is the proclamation of the Gospel and her law is the salvation of souls. The specific mission territories are named for their particular characteristics of geography, access, culture, self-support, among others. The lay faithful are called to exercise canonical substitution in the legitimate absence of clerics and when necessity and usefulness so require. That canonical substitution (c. 230&1) frames a number of functions or faculties that allow lay people, suitable and well-trained, to be agents of evangelization in many functions that clergy perform.