The latest ACT Public Service - State of the Service report shows the number of bureaucrats in Mr Barr's Chief Minister, Treasury and Economic Development directorate grew by 47 per cent as another 739 public servants were added to the organisation.

The centralisation of workers in the directorate came in a year when expansion across the territory bureaucracy was a modest 1.6 per cent, or a net increase of 301 full-time equivalent staff.

At the same time as the ACT's peak directorate collected hundreds of extra workers, others lost staff.

Almost a third of employees were taken out of Environment and Planning Directorate and one in six was stripped from Justice and Community Services, while the Territory and Municipal Services workforce - which looks after roads, rubbish and nature reserves - was reduced by a tenth.

The largest workforce in the ACT public service, at the Education and Training Directorate, remained almost static at 5,146 full-time equivalent staff.

It is believed the concentration of power in Mr Barr's directorate comes after the creation of Access Canberra - the catch-all shopfront for all ACT residents which, for example, now dealt with fines once administered by Justice and Community Safety.

ACT opposition leader Jeremy Hanson said the concentration of power sent the message Mr Barr did not trust his own ministers.

"As we saw with Kevin Rudd, when leaders of government try and control everything, the government becomes dysfunctional and it appears Andrew Barr is making similar mistakes," Mr Hanson said.

An ACT Government spokesperson said Access Canberra in December 2014 brought together all of the regulatory functions across government under one new agency.

"CMTEDD leads the ACT Public Service, facilitating the implementation of government priorities and driving many new initiatives, and is therefore the logical place for a cross-government agency like Access Canberra to be located," the spokesperson said.

"Furthermore the establishment of the Asbestos Response Taskforce in July 2014 has also contributed to a growth in staff numbers in CMTEDD."

Meanwhile, ACT Minister for Women Yvette Berry said the report showed the territory bureaucracy had made large gains in closing the gender pay gap.

"The ACT Public Service continues as an employer of choice for women with statistics recently released in the ACTPS State of the Service Report 2014-2015 showing that the gender pay gap has closed to only 2 per cent," she said.

"In 2015 the ACTPS remains one of the nation's best performers for women in closing the gender pay gap.

"Nationally women earn 17.9 per cent less than their male colleagues, while in the ACTPS women are paid 2 per cent less.

"The ACTPS is also performing better than the broader ACT labour market where the gender pay gap is still 11.7 per cent."

The territory public service, of which females made up of 65 per cent, has an even higher proportion of women then the federal bureaucracy, of which 60 per cent were women.

"In 2015 the ACTPS has 13,593 female employees," Ms Berry said.

"This is approximately 17 percentage points more women than the overall ACT labour force (48.3 per cent) and approximately 19 percentage points more than the Australian labour force (46.1 per cent).

"In executive and decision-making roles, the ACTPS continues to demonstrate leadership with women holding 42 per cent of senior executive positions."

In the ACTPS six out of eight directors-general, including the head of the service Kathy Leigh, are women.