He speaks of a "need for change, the need to cut the pack differently and to reconsider what we are about". There are about 170,000 items in the collection, predominantly Australian, but only a small number can be on show at any one given moment. Until the ambitious stage two of the building expansion is completed (and the plans are still on the drawing board and unfunded), it is not feasible to attempt a comprehensive chronological display of Australian non-Indigenous art. The strategy that he has adopted is to present Australian art as a series of snapshots that constantly change. "Every room is like a mini thematic exhibition based on the Australian experience and every six months half of the rooms will be replaced, so that within a year all of the rooms will change." Key works in the collection will remain permanently on display, but most will be rotated and over a period of time more of the collection will be shown than ever before. Part of this approach also involves a deliberate mixing of mediums with paintings and sculptures sharing the space with photographs, drawings, prints and the applied arts.

As part of the general process of dissolving boundaries between categories in art, there is also a blurring of lines between Indigenous and non-Indigenous Australian art, especially when artists do not come from traditional tribal areas. I have long argued that it is becoming increasingly untenable to segregate the art of Indigenous Australians from the art of other Australians of different origins. In the past, when Indigenous art was battling for recognition and was struggling to be heard, it made sense to foster this development in isolation. Under present circumstances such segregation hampers the development of Aboriginal and Torres Strait Islander art and hopefully over the next decade the gallery will move to more seamlessly unite the Australian collection.

The most striking change to the appearance of the gallery display lies in the bringing of Australian art downstairs and taking the international collection upstairs. It is a risky strategy, but one that I personally approve of and have argued for over a number of years. However, it does mean that a visitor wishing to see Blue Poles will have to see a good dose of Australian art along the way and that in itself cannot be a bad thing. There was a marketing argument advanced some years ago that there exists a category of "the 20-minute visitor", one who pops into the gallery, while the bus is waiting, to see and photograph the so-called destination works, visit the gift shop and then they are off to the next "must-see" venue. Now they are more likely to see Sidney Nolan, John Brack, Fred Williams and Margaret Preston, than the New York School. There has also been a change to the downstairs "sunken gallery" that will reopen in late March 2016 as a new gallery of contemporary Asian art practice.

Together with this there has been a certain chronological reorientation of the Australian galleries, so that when you enter from the side of the main entrance, you actually start with contemporary art and then chronologically work backwards to colonial art. It can be argued that Australian art over the past 25 years has been considerably more interesting and accomplished than non-Indigenous Australian art during the first 25 years after the landing of the First Fleet. In the same breath one could say that Sally Smart and eX de Medici, in their most recent work, are more engaging and challenging artists than the so-called Port Jackson painter, Thomas Watling or Joseph Lycett.

Australian colonial art also looks quite different from its earlier incarnation upstairs with the deep burgundy walls replaced with the "white cube look" and, in most instances, the density of a multitiered salon hang is now replaced by a more spacious breathing space. The Glovers and von Guerards glow with a striking luminosity against the new backgrounds and the Australian Edwardians also appear quite splendid and striking. It was Sir Nicholas Serota, the director at the Tate, who a couple of decades ago popularised at Tate Britain the idea of a non-chronological display for telling the story of British art, for example, by juxtaposing a Tudor portrait with a Lucian Freud portrait as a strategy to make one see art differently. Something of this philosophy is creeping into the new display, where art from different periods is being brought together. The thematic rooms, including those dealing with Federation, surrealism, living in a machine age, isolation and loss in Australia and surf, sun and sex, all individually bring a new perspective to aspects of Australian art. Amongst my favourites are the John Brack and Fred Williams room and the wall of Australian prints and photographs displayed four rows high.

Upstairs, in the new galleries of international art, there are three striking changes. Firstly, nearly all of the secondary walls have been removed allowing for a greater flow and longer viewing distances, but as a consequence reducing the wall space available for display. Secondly, the gallery is gradually converting its lighting system to LED lighting, which means that paintings such as Blue Poles glow with a luminosity and intensity that previously had been unimagined. Thirdly, there is a plethora of new acquisitions on display, including the new Gilbert and George, a dedicated display of the Ken Tyler collection and a sensational presentation of part of the David Hockney collection. The gallery's famous collection of modern international art, that is unrivalled in this country, has never looked better.

With this new display the gallery is boldly announcing that it is open for business and invites you to see its collection as you have never seen it before. With the projected constant changeovers, the gallery declares that there will always be something new to see.

The new-look National Gallery of Australia opens on December 1.