The new chair of the National Capital Authority rejects suggestions she has assumed the role at a time when the organisation has been rendered impotent, hamstrung and subservient to the ACT government.

Melbourne architect Shelley Penn says those claims by Walter Burley Griffin Society president James Weirick are a flawed interpretation of the federal government's response to the Hawke review of the authority.

''There's a perception there's been a weakening of the NCA but that's not the case,'' she says.

A review of the NCA by former Defence Department secretary Dr Allan Hawke recognised the authority's role in representing the Commonwealth's interest in the planning and development of Canberra. But it also saw opportunities to reduce duplication with the ACT government's planning structures and clarify areas of responsibility.

The federal government in its response agreed, saying it would work with the ACT government to ''simplify the Commonwealth's national capital planning system and better recognise the role of ACT government''.

Key in that work is redrafting the criteria for determining issues of national significance within the territory and incorporating them into the National Capital Plan, essentially defining more clearly the NCA's areas of responsibility.

Writing in The Canberra Times last month, Professor Weirick made plain his view: that the National Capital Authority had capitulated.

''It's all over. Control of the national capital is to be handed to the ACT government. The ACT is to be divided into two jurisdictions with the National Capital Plan subservient to the Territory Plan,'' he wrote at the time.

But that's '' just plain wrong'', Penn says. ''We're now entering into a review of the [National Capital] Plan and part of that is going to be looking at the jurisdictional boundaries. So that hasn't been decided yet.''

Penn says the authority will be conducting the review - with reference to the ACT government and the community - to define the areas of national significance. There have been suggestions in the past a new system could take a decade to take effect. Penn says it may take five years to lock in but believes within 12 months something tangible will be put before the community for feedback.

''Depending what comes out of the review, it's quite likely we will pass power in some areas to the ACT government but that's not about just reducing our purview to the [Parliamentary] Triangle. It's not at all about that,'' she says. ''For example, the landscape character is absolutely critical to Canberra. It's the hills and the ridges and the open space system. I believe that's critical. So we don't want a situation where we have a pristine, highly managed Parliamentary Triangle and the rest is doing something else. So I want to allay that concern. It's certainly not how we see it.''

Penn also rejects suggestions the federal planning instruments are now subservient to their ACT counterparts or that the NCA will now have to kowtow to the ACT government.

''I think we have to accept that we won't always agree,'' she says.

Penn, a 47-year-old mother of two who has practised architecture both privately and within government, was appointed chair of the authority on June 14 after almost eight months acting in the role.

She replaced Professor Don Aitkin, a long-time Canberran who had held the position for three years. Penn understands there may be some scuttlebutt about someone from outside Canberra being made chair of the board. She will draw on the views of Canberra-based members of the board but also bring a national perspective to the role.

''I just have a passion for Canberra and the quality of the place and how I do believe it can grow and hold on to these wonderful qualities it has,'' she said.

In response to the Hawke review, the federal government has also invited the ACT government to nominate a member of the board to represent the interests of the Canberra community, someone with a ''long-standing and lasting interest in the national capital and a connection to the people of Canberra''.

Born in Melbourne, the daughter of a road-building contractor and stay-at-home mum, Penn was encouraged to consider architecture by a careers counsellor in her final year at Kildington Girls Grammar and eventually enrolled at Melbourne University. She went to Japan during her third year when her love for architecture really ignited.

''I saw some amazing contemporary architecture there that really moved me and really gave me the sense for having a positive impact on the world and enriching life,'' she said.

Penn now has her own practice in Melbourne where she works from home but has worked for both the NSW and Victorian governments, including as the first Associate Victorian Government Architect. She was recently involved in reviews of the planning process for the NSW government's massive Barangaroo project in the heart of Sydney. Penn is also the national president of the Australian Institute of Architects.

Her partner is Mark Edgoose, a silver and goldsmith who works at RMIT and whose pieces are in several collections, including that of the National Gallery of Australia. They have two sons, Harry, 10, and Will, eight. (''We're not royalists,'' she says, with a laugh. ''The names were a coincidence.'')

She believes a big role of the NCA is promoting Canberra as the national capital and says she rarely has to defend the place to her friends.

''Most people I know are in architecture and landscape architecture and know it's a fantastic place,'' she says.

''Sometimes people make silly comments and I think that comes from a place of ignorance.''

After some tumultuous years under the Labor Government when funding was cut to the bone, Penn believes the authority now has the support of the government and especially Regional Australia Minister Simon Crean, who announced $11.9 million in funding for the authority in this year's budget.

''I think we're very well supported,'' she said. ''I think our minister, Simon Crean, completely gets the significance of the national capital and the value of what we're doing.''