Godparents have a special role in Baptism.  Along with the parents, they present the child to the Church. It is also their responsibility to assist the baptized person to lead a life in harmony with Baptism and to fulfill the obilgations flowing from it. The prerequisites are that the godparents are persons who:

1. are Catholic, have been confirmed, and who are currently receiving the sacrament of the Eucharist;
2. are at least sixteen years of age (an exception may be made by the parish priest); 
3. lead a life of faith in harmony with the function they are undertaking and have the intention of undertaking this function; 
4. are not parents of the child;
5. are not bound by a legitimetely declared or inflicted canonical penalty.  

In light of the Code's (Code of Cannon Law) directive that godparents are to lead a life of faith in harmony with the nature of this public office in the Church, Catholics who are in an irregular marriage are not to serve as godparents. 

There need be only one godfather or godmother, although it is common practice to have one of each.  A baptized person belonging to a non-Catholic ecclesial community may be admitted only as a Christian witness to Baptism; the function of the Christian witness in such a case is to attest to the actual celebration.  There must always be a leaset one Catholic person who has the office of godparent.                                 Sacramental Norms and Policies, Archdiocese of Washington