In the Anglican Church we have three formal ways of affirming our faith - confirmation, reception, and reaffirmation.
Those who have been baptized as infants or young children often reach an age when they wish to take ownership of the promises made on their behalf by their families and godparents or sponsors. This affirmation of faith is called confirmation. The service is among the rites of the Anglican Church at which the bishop presides.
Others who were baptized and confirmed in another Christian tradition may find themselves drawn to the Anglican Church and wish to be formally recognized as a member of this denomination. These people are welcomed into the Anglican Church by the bishop through a rite called reception. This rite does not suggest that the person's previous Christian life was not meaningful or sufficient. Rather, it serves to acknowledge formally the move from one Christian family to another.
Reaffirmation is a rite available for those who have been confirmed or received but who, for a variety of reasons, wish to reaffirm their baptismal vows. For some people, this desire may come because of a long separation from the church. Others may want to reaffirm their vows to celebrate a time of significant spiritual renewal in their lives. The bishop, as the chief pastor of the local church, presides at the rite of reaffirmation.