If you are intending to marry a partner who is not a Catholic but who has been baptised in a Christian church, your partner will need to obtain this certificate from his or her own church of baptism. If your partner has not been baptised, is a member of another faith, or has no religious faith you will require a special dispensation from the Bishop to have a Catholic wedding. If you or your partner have been married before you will not be able to have a Catholic wedding unless the marriage was one which the Catholic Church does not recognise as truly valid. (You would need to consult St Patricks's or your own local Catholic Parish Priest about this).

Catholic weddings are either celebrated with a Nuptial Mass – which is obviously a rather more splendid sort of wedding, with hymns, Eucharistic Prayer and Holy Communion, or they are celebrated as simple services outside Mass with or without hymns and Holy Communion. If either or both of you prefers not to or feels unable to receive Holy Communion (eg because one partner belongs to a different Christian denomination) it is often better to choose a marriage service outside Mass - though not being a Catholic does not automatically mean your partner cannot receive Holy Communion if he or she shares our belief in its meaning. If a large number of the congregation will wish to receive Holy Communion, some special arrangements will need to be made to provide Eucharistic Ministers as well as enough hosts, and St Patrick's will need to be consulted about this well in advance of the Service.