Confirmation is the sacrament in which the Holy Spirit is called down upon the person being confirmed through the imposition of hands and anointing with Chrism by the bishop. Like baptism, confirmation imparts a special mark or character on the soul, and, also like baptism, it can only be received once in a person’s lifetime.
While confirmation can be administered at any age, the general practice in the United States is to administer confirmation to adolescents and older people who convert to Catholicism. At the Easter Vigil service, confirmation is administered by the priest to converts who were baptized previously, even if they were baptized in another Christian tradition. Otherwise, the bishop is the ordinary minister of confirmation.
Confirmation can be thought of as a “coming of age” sacrament, and people who receive it are expected to have undergone religious education. The bishop informally quizzes the candidate for confirmation on basic articles of faith. As with baptism, the person being confirmed has a sponsor who has the responsibility to encourage the individual in leading a holy, Christian life.
Click here for USCCB info on this sacrament