Australian Computer Society CEO Bruce Lakin has cited differences in opinion with other ACS executives for his shock resignation from the leadership team.
Lakin is the second chief executive to leave the CEO position in the past two years. ACS declined to comment on the circumstances of his departure.
Speaking to iTnews after the society's Christmas party on Friday, Lakin said he had resigned and would become an ordinary ACS member from April 2011.
"After being with the society for a bit over a year, there were differences between myself, the president and management committee over governance and strategy," Lakin said.
"Under the circumstances, it is best for the society that the CEO steps down."
Lakin said the society had made "substantial progress" in the past year, amassing a record high of 18,000 members and organising the World Computer Congress, which attracted 1,200 delegates.
ACS president Anthony Wong today said he had commenced recruiting for a new CEO, in accordance with his email to members last week.
Wong thanked Lakin for his "significant achievements", stating: "Bruce leaves with our best wishes and our gratitude for his contribution to the Society.
"He has achieved significant improvement in the operations of the Society and advanced the relevancy and value proposition of the ACS to its members and key stakeholders, resulting in strong membership growth."
But Lakin also had a number of regrets about his time at the ACS.
"When I came here, I came here with ambitions of taking the society further than we have done together," he said.
When Lakin steps down in April, he will have spent less than 18 months as CEO - a few months longer than his predecessor Kim Denham's 14-month stint.
"It is disruptive for the society to have a couple of CEOs in quick succession," Lakin said.
Lakin said he planned to continue working in members' best interest in the coming months, while seeking new job opportunities and handing over the role to his successor.
"I've had a long career in ICT, which I don't plan to end," he said.