The Land Development Agency's outgoing deputy chief executive, Dan Stewart, has made the move back to the private sector but remains committed to progressing the city.
Mr Stewart left the agency last month after 14 years in the public service to lead the Canberra office of Elton Consulting.
He said while he had enjoyed his time in the public service it was time to take a new opportunity to contribute to the growth and development of Canberra.
"I personally believe there's no better role in government to influence or inform the direction the city's taking than the one I've just departed," he said. "It was the most exciting role I held in government by a long shot."
Mr Stewart named the ambitious City to the Lake plan, the Yarralumla Brickworks and the Kingston Foreshore as the standout projects he'd been involved in.
The brickworks proposal, which he had previously described as key to the territory's urban renewal program, was dramatically slashed at the end of August.
The Land Development Agency has reduced the number of dwellings planned for the site from 1800 to a maximum of just 380 and scaled down the proposed development area and building heights.
While Mr Stewart maintained the original plan for the brickworks would have worked he understood the need to compromise with the community in order to progress the plan at all.
But he said the site could hold many more dwellings than what was now being proposed.
Mr Stewart said the challenge for the ACT government going forward was to get the ratio of infill and greenfield land release right.
"Ultimately we don't have an unlimited supply of greenfield land and we have a growing population so there is a point in time where Canberra will need to grow from the inside out rather than the outside in," he said.
The only way to achieve that inside-out growth was through urban renewal, metropolitan redevelopment and infill.
"We have to get it clear in our own minds as a community about where the appropriate locations for that infill are and what is acceptable and appropriate in terms of density and height and I don't think we're there yet," Mr Stewart said.
Elton Consulting has been in the ACT for more than 25 years and is currently working with the Riverview Group to plan the West Belconnen development.