In the Catholic church, marriage between a Catholic and a baptized non-Catholic Christian requires express permission from the local bishop. Marriage between a Catholic and a non-Christian requires the bishop's express dispensation.
In the Catholic church, marriage between a Catholic and a non-Catholic baptized Christian is called a mixed marriage. When a Catholic marries a non-Christian, the term employed is "disparity of cult." Canon law, the law of the Catholic church, requires the permission of the bishop in order for the marriage to be licit, though the marriage is considered valid even if performed illicitly. The wedding may take place in a normal Catholic ceremony, and a non-Catholic minister may also address, pray with or bless the couple. With the bishop's permission, the wedding may also take place in a non-Catholic ceremony, with a priest present.
With a disparity of cult, the bishop must provide a dispensation from the usual canon law prohibition against such marriages in order for the marriage to be valid. The bishop grants permissions or dispensations at his discretion, for just cause, and with the understanding that both parties understand and do not object to the Catholic understanding of the nature and purpose of marriage. In addition, the Catholic party must promise to continue practicing the Catholic faith and to raise any children resulting from the marriage as Catholic. The other party must be made aware of these promises but is not required to make any.