Edinburgh, Scotland - The wedding of Martin Reijns and Karen Watts will ring the changes
Britain's first legally recognised humanist wedding is to take place in Edinburgh at the weekend.
Rules on the venues in which Scottish couples can marry had been relaxed, but services still had to be carried out by a minister of religion or registrar.
Karen Watts and Martin Reijns will be united by a humanist celebrant at the city's zoo after it was agreed that the restriction was discriminatory.
Humanist representatives have demanded the same changes in England and Wales.
Legal force
Humanists believe that people can live ethical lives without religious beliefs.
Before the changes, anyone choosing a humanist wedding had to have a civil ceremony beforehand to legalise the marriage.
Mr Reijns, 27, from the Netherlands, and Ms Watts, 29 from County Clare in Ireland, live in Polwarth, Edinburgh.
Ms Watts, a community development worker, said: "For us there was never the option of having a religious wedding ceremony.
"Neither of us are religious and it would have felt hypocritical to get married in a church.
"But at the same time we wanted something more meaningful than the legal civil ceremony."
The decision by the Registrar General for Scotland means 12 registered celebrants of the Humanist Society of Scotland are now authorised to conduct legal marriages.
The secretary of the organisation, Ivan Middleton, will be the celebrant conducting the Edinburgh Zoo wedding.
He said: "For 15 years we have been writing to various Registrars General, our argument being that under European legislation humanists who had a philosophy were being discriminated against by not being able to have legally-binding marriage ceremonies."
'Impatient'
Scotland's Registrar General Duncan McNiven said the change puts the humanists on a par with the heir to the throne.
He said: "UK legislation requires us to interpret the British law, including Scottish marriage legislation, in a way that is consistent with the European Convention on Human Rights.
"The Prince of Wales used that to put beyond doubt the fact that it was okay for him to have a civil marriage and we are using it to put beyond doubt that humanists can legally marry people."
The Registrar General for Scotland has authorised 12 registered humanist celebrants to conduct legal marriages.
Meanwhile, the British Humanist Association has written to the Lord Chancellor calling for the Scottish ruling to be recognised in England and Wales.
Executive director Hanne Stinson said: "Now that Scottish humanists have won their rights, we are impatient for action."
She said the law in England and Wales was more complex and could probably not be reinterpreted as it had been in Scotland, therefore legislation would be needed.