"A 6-year-old autistic boy said his first ever words after one ride: Harry is fine. Riders start with about five people helping them and get to a stage where they are riding by themselves and even competing."
Located on the corner of Purnell and London St, RDA has been operating in Whanganui for 45 years.
Originally started after World War II as a solider rehabilitation programme nationwide, RDA works with children and adults who face physical, intellectual, emotional and social challenges.
Mr McLeod is one of the many volunteers who help keep the programme afloat.
He said every year more than $100,000 worth of donations are needed to keep RDA running.
"The horses cost money, they need feeding and grooming, the paddocks need to be kept maintained, transport costs money ... when you start listing it all, it really is a lot."
But the RDA Whanganui manager, Wendy Sellars, said local businesses, community members and even out of towners have shown a huge support.
"If it wasn't for volunteers like Chris this place wouldn't be here today, but every year it becomes more of a struggle."
Mr McLeod said there is some relief in hanging up his suit and tie at the end of the day and putting on his gumboots to help out.
"It brings you back down to earth. Working with these kids is just as benefiting for me as it is for them."