The stars of Riverdance are taking to the streets of Dublin today for a dance-athon.
They're taking part in 12 hours of continuous dance in aid of the Alzheimer Society of Ireland.
Over 500 dancers from dance schools across Ireland are joining in the event outside Dublin's Gaiety Theatre.
Riverdance executive producer Julian Erskine says it's very close to their hearts.
"Our general manager for many years. a gentleman called Ronan Smith, has been diagnosed with Alzheimer's.
"So it's as a tribute to Ronan, who will be with us today, that we're trying to heighten awareness of what it's like living with Alzheimer's and living with people who have Alzheimer's".
He says it's going to be a really exciting event.
"It's the anticipation of seeing Riverdancers out of their comfort zone - you're not going the Gaiety or into a theatre to see them.
"They're out on the street... it couldn't be any more up close and personal cause you're a couple of feet away from the dancers.
"And the dancers love it too, because they have that direct, personal connection with the audience".