The action started in the annual J and T Hickey Charity Sheep dog trial this morning, held as usual in the Riding Cub for the Disabled complex at the Showgrounds Park.
The 120 runs will be divided up today and tomorrow, ahead of a final run-off on Saturday morning.
A feature this year will be the number of novice competitors, with 17 young triallists involved.
The event supports the RDA, the Trust Tairāwhiti rescue helicopter, Idea Services and CCS Disability Action.