"In 2000 Mary and I were running this business with about three staff when Nick decided to not renew a contract with a merchant banking firm in Wellington," Don Stewart said.
"We wanted to go away overseas for a while, which is pretty hard when you are the principal adviser of a firm. At that point we had both risk management and wealth management work.
His son offered to oversee the business "and we came back he said, 'I have had a ball over the last three months - can you now give me another six months?'"
"I've been reflecting on this because we spend a lot of time advising people on succession planning.
"Mary and I are quite lucky ours is so smooth and initially instigated by Nick."
Staff numbers grew with the business and in 2006 Stewart Group bought the building Don Stewart worked in as a National Mutual agent, renovating it to fit its 16 staff.
They found the hand-sized Prickle Patch honey sticker on the pillar, where it sits today.
A the recent 30th anniversary celebration Don Stewart said he was as pleased with the decision to go independent as he was with its smooth succession.
"Our advice these days is client-centric - we are not driven by fund managers who are saying we need you to push this product or facility. We are not interested in that and are fee only in all of our advice.
"I don't think I would have envisaged at age 24 I would be talking to you now, going on 68, with a business of this size but the key was succession planning which enables me to now work four days a week and delegate. I have great support people working with me on the cases I choose to deal will with. So it has worked well."
In July last year Stewart Group acquired Wellington firm Red Wealth Managers.
In 2015 Stewart Group launched Boutique Advisers Alliance (BAA), an advisory service for fee-only Independent Financial Advisers.