The first step is delivering a great customer service experience for each client and the second is to make the transition from a one-off transaction to an ongoing business relationship.
He told The Daily Post relationship building was the key to changing a positive customer experience into dollars in hand.
"If a client has a great experience, they will return to the business and tell 10 friends. If only one of those friends becomes a new client, that's a 100 per cent return on that relationship."
The 2011 Westpac Rotorua Business Excellence Awards are this Friday and Duncan has been working with finalists. He said winning the customer service award in 2009 and 2010 had been excellent for his own business and it was positive talking to other businesses with such a strong customer service focus.
"It is great seeing these businesses achieving excellence benchmarks, but they are the minority. Customer service excellence is a clear point of difference in the market."
Duncan said New Zealand's complaint culture needed to be "turned around".
"If a Kiwi has a bad experience, they won't say anything at the time, but then they will call 10 people and tell them about it. Complaints need to be seen as constructive feedback."
He said customers needed to be more honest if they expected service levels to improve and business owners and employees needed to be less defensive about negative feedback, make the client feel as if they have listened and then use the criticism to improve. "This is becoming even more important in these days of social networking, which can create or destroy your business."