Mr Harris says the Skilled International Alumni Project being developed in partnership with educational institutions throughout the region will be operational by June.
He describes the scheme - which is being greeted enthusiastically by secondary schools and tertiary providers - as potentially "one of the most significant economic development [projects] ... we could undertake".
"I think it has massive potential because most alumni have strong allegiances to their school and the region," Mr Harris said.
"It could give us an edge, taking us from being on the edge of the world to having connections with people around the globe."
The alumni project is built on the assumption those most likely to move to Otago or invest in it are people with historic ties, either familial or educational.
To foster those links, the city council is developing a database to help educational institutions track and build relationships with former pupils and students.
The city council will use the institutions' databases to feed information about the region and investment opportunities to alumni throughout the world.
A communications co-ordinator for the project will be appointed soon.
City council business development adviser Deb Sutton, who has been working on the project for the past year, said at least eight Dunedin secondary schools would be involved initially.
She expected it would quickly become region-wide.
The University of Otago has its own alumni programme and Otago Polytechnic is developing its own database but both were working closely with the city to help alumni foster closer relationships with the region, Ms Sutton said.
The initiative was "a fabulous thing", Otago Polytechnic business-relationship adviser Bevan Rickerby said.
It would hopefully result in more alumni returning to the city to set up business or finding opportunities to invest in the region, Mr Rickerby said.
Otago Boys High School Foundation chief executive Doug Kamo described it as "absolutely sensational".
"Any educational institutions that are succeeding have an extremely strong alumni programme behind them because you can't just depend on government funding," Mr Kamo said.
"From the city's perspective this is a fantastic opportunity to enable those now living outside the city to re-engage with it."
OBHS has had an alumni programme for six years.
Otago Chamber of Commerce chief executive John Christie said Dunedin was "fondly remembered by those who have studied here" and the city had many examples of "people who have lived abroad who have come back here to live".
"The acid test will be seeing the fruit of such an initiative ... It is one piece of the jigsaw puzzle," Mr Christie said.
Mr Harris said identifying commercial opportunities for alumni to participate in was a key goal in ensuring the success of the project.
"Research has shown a huge proportion of expatriates intend to come back but won't unless there is something to come back for. So we have to give them the reasons to come back.
"The challenge will as much be getting Otago businesses to ask for the help they need."
The project has received $126,500 funding from New Zealand Trade and Enterprise, and $50,000 from the council, Tourism Dunedin, Otago Polytechnic and Otago Forward.
