§1. By the witness of their life and word, missionaries are to establish a sincere dialogue with those who do not believe in Christ so that, in a manner adapted to their own temperament and culture, avenues are opened enabling them to understand the message of the gospel.
§2. Missionaries are to take care that they teach the truths of faith to those whom they consider prepared to receive the gospel message so that they can be admitted to receive baptism when they freely request it.
Source: Code of Canon Law (Vatican.va)