The Federal Government has appointed Commonwealth Solicitor-General Stephen Gageler to the High Court.

Mr Gageler will replace Justice William Gummow, who will retire in October after 17 years on the bench.

Mr Gageler has served as Solicitor-General since 2008, and before that he worked as a barrister in Sydney.

Announcing the appointment today, Attorney-General Nicola Roxon said Mr Gageler's previous experience made him a stand-out for the role.

"This is not an easy choice because we are blessed with a lot of very capable lawyers and, of course, many of them were considered closely," she said.

"I think his mix of experience, his commitment to public life in terms of the workings of government, a lawyer who has been interested in administrative law and constitutional law since his very early days, [he] is obviously someone with particular experience that is called upon regularly in the High Court."

Mr Gageler represented the Commonwealth in the High Court last year when it blocked the Government's so-called Malaysia solution on offshore processing.

But he enjoyed more success last week when the High Court threw out a challenge from tobacco companies to the Government's plain packaging laws.

Ms Roxon says those cases had no bearing on her decision.

"The important decision being made today is to get someone who has legal talent and skills of the highest calibre," she said.

"Obviously Mr Gageler has appeared in many cases for the Commonwealth, and really none of those have been the turning point for us in making this decision."

Shadow attorney-general George Brandis says Mr Gageler was one of the five people the Coalition recommended for the job.

"As part of the consultation process earlier this year, at which a range of interested parties were solicited for their views as to suitable appointees to the High Court, I can tell you Mr Gageler's was one of the five names on my list."

NSW Bar Association president Bernard Cole has also welcomed the announcement, saying Mr Gageler has one of the country's finest legal minds.

Change on horizon

High Court justices have to retire at the age of 70, meaning major change is on the horizon.

Justice Dyson Heydon will leave the bench in February next year. Two more will follow in 2015.

When seeking nominations for the coming vacancies earlier this year, Ms Roxon called for a wide net to be cast.

Only four women have ever served on the High Court bench; traditionally it has been dominated by white, male former barristers or judges from Sydney or Melbourne.

"I always have said that the best person for the job would be chosen, and it's not going to surprise you that on some occasions that is going to be a man from Sydney," Ms Roxon said.

"In other occasions it's going to be a woman from another part of the country, and sometimes both."

And while it will probably not help him during High court debates, Mr Gageler also has a black belt in Taekwondo.