"Rachel posed for hundreds of photos, with many delegates being fans of her television show [Tour of Beauty]."
The expo is attended by some 4700 of the who's-who of the global travel industry.
While Sir John Kirwan was working with the ATEED on a domestic level, Hunter was its first international ambassador. At this stage, the arrangement was for a year.
"Based on global trends, with ad blockers hiding more traditional forms of advertising and consumers becoming more disengaged with brands preaching to them on social media, the opportunity to instead work with influential individuals like Rachel provides an important link to consumers," ATEED said.
"People are less swayed by blatant advertising and prefer to make purchase decisions by researching brands themselves or on recommendation from someone they trust, and Rachel's profile and passion for her home city of Auckland makes her a great ambassador for the region."
Her roles would include appearing at VIP events, as a guest speaker, MC or co-host to promote the city.
She would also provide sound bites, images, clips and comments about Auckland while utilising her personal social media channels to let followers know about the city.
"Rachel will be promoting Auckland as a great place to visit, study, invest, do business and live."
Hunter, who grew up in Glenfield but now resides in Los Angeles, said she was a proud Kiwi and would always call Auckland home, according to the ATEED statement.
"It's a beautiful place. The immediate connection you can have with nature, the city and the diversity of the people makes me proud of who we are as New Zealanders, and this is something I want to share with the world," she said.
Outgoing ATEED boss Brett O'Riley said Hunter's appearance at the event offered an "unparalleled" opportunity to showcase Auckland to such an influential group.
"Rachel is well-known on the international stage for her long modelling career as well her passion for the environment and from her Los Angeles base is in a prime position to influence the premium US visitor market," he said.
According to Statistics New Zealand data, there were over 262,000 visitors US visitors to Auckland in the year ending June 2017 -- up 31.6 per cent on the previous year.
ATEED said they had contributed $480 million to the regional economy, adding that air connections between Auckland and the US had never been so it was in a prime position to keep boosting visitor numbers.
Hunter, an avid environmentalist, also acts as an ambassador for the animal welfare Born Free Foundation and has set up a fund to help save endangered gorillas.
The deal with Hunter is for a year. An Ateed spokeswoman said: "This includes appearances at VIP events as an Auckland advocate as a guest speaker, MC or co-host to deliver Auckland's key messages around tourism, events and economic development.
"Rachel Hunter will also provide key soundbites, images, clips and comments promoting Auckland. She will promote Auckland and her activity with ATEED on her personal social media channels"