Long serving Liberal Vicki Dunne will retire after election

There wouldn't be many other politicians in the country with a more unenviable record of time spent in opposition.

She's been a member of ACT Parliament since 2001 and for all that time Labor has been in power.

Almost 20 years in opposition takes its toll, but Mrs Dunne says she's still been able to get things done.

She will today announce she will be retiring from politics at the end of her term in 2020, a plan she and husband Lyle have had for a while.

"They say most people leave politics either being bundled out or in a box and I wanted to go at a time of my own choosing," Mrs Dunne said.

She's often seen as one of the opposition's best performers during question time and when it comes to being on top of her portfolio.

Mrs Dunne credits this to her many years in the building and her loyal and dedicated small team.

And while she would have loved a chance to be an MP in government, not opposition, she's pretty pleased with what she's been able to achieve.

"Sometimes in a large parliament, opposition members become somewhat irrelevant but that isn't the case here. We're a boutique parliament and the voice of the opposition can be very powerful," she said.

Mrs Dunne has held almost every portfolio possible during her time in Parliament and is currently the opposition's spokeswoman for health.

While former Health Minister Meegan Fitzharris suggested the opposition were "not their best selves" during question time, Mrs Dunne said she was only ever focused on making the health system better.

"She was wrong, I really did go in with the best intentions in the world by saying 'can we do this together'," Mrs Dunne said.

She said she and her staff were inundated with personal stories about the health system which took a big toll.

"The staff culture stuff was harrowing, it was harrowing for my staff who took the calls," she said.

Chief Minister Andrew Barr has stepped up his rhetoric around some Canberra Liberals' conservatism, saying it puts them at odds with progressive Canberra.

Mrs Dunne has well known socially conservative views on issues like abortion, euthanasia and gay marriage.

But she doesn't believe local politics should be driven by ideology.

"It doesn't matter how progressive you are if you can't deliver basic services you aren't doing your job,"she said.

She thinks the Liberals are in with a chance at next year's election - but she also thought that for the two elections prior.

"We have to garner another 5000 votes. It's within reach," she said.

Mrs Dunne said ACT Liberals were incredibly united - but that had not always been the case.

She said there were times when the opposition could only be described as a joke.

But that all changed, according to Mrs Dunne, when now federal senator Zed Seselja was made opposition leader.

"We behaved badly, but from 2007 onward the opposition has been an extraordinarily well oiled machine unbelievably united and it is just a complete joy to work for these people," she said.

"It was ego driven, when politics is ego driven it's not good for people."

While she and former Chief Minister Jon Stanhope were once great sparring partners, they've found more common ground in recent years, specifically in their criticisms of health in the ACT.

Mrs Dunne rates Mr Stanhope and Simon Corbell as the most effective Labor members she's worked with.

She's looking forward to starting the next chapter of her life with husband Lyle and children in Canberra, with more than a bit of travel planned.

But she will still be involved in the party and hoping the ACT's 19 year Liberal drought will be broken in 2020.

"I'm not going to go there and say I'm an elder statesman you have to listen to me, but I will be a sounding board," she said.

"I will be as available as the party wants me to be."