All five Garth Brooks concerts have been called off.
Aiken Promotions says it has exhausted all avenues regarding the staging of these events at Croke Park - and no concerts will be taking place.
The performances were due to take place later this month.
Aiken Promotions - who says it's very disappointed for the 400,000 fans - says the ticket return process will be outlined tomorrow.
Ticketmaster says the process will be made as simple and convenient as possible for customers.
However it's asking customers to be patient due to the scale of the operation which it says is unprecedented in the Irish entertainment industry.