When you ask about James Holloway, most people tell you about his passion for motorbikes, not his work as the director of the Scottish National Portrait Gallery. But while he admits that his "obsession" with motorbikes persists, what is really exciting him at the moment is the gallery's £17.6m redevelopment.

The gallery, one of four museums operated by the National Galleries of Scotland (NGS), closes next month, but Holloway is already looking forward to its reopening in 2011. "We are all hugely excited and I just want to see the collection on the walls and see what it looks like. It's going to be fantastic."

The project is known as Portrait of a Nation, and there is still a lot of work for Holloway to do before he can sit back and admire the results. The Heritage Lottery Fund has committed £4.8m, the Scottish government has given £5.1m, and another £1.8m has been raised from other sources, leaving £5.9m that he still needs to find.

Holloway's boss, NGS director-general John Leighton, believes that the momentum created by the £50m it has just raised in partnership with London's National Gallery to secure Titian's Diana and Actaeon will make it easier to attract funds for the portrait gallery.

But these are tough economic times and National Museums Scotland is also hunting for backers to complete the funding package for its £46m Royal Museum Project, also due to open in 2011.

Nevertheless, the plans for the portrait gallery are much-needed. It was the world's first purpose-built portrait gallery when it opened in 1889, but is looking a bit tired now. For many years it shared the building with the Society of Antiquaries of Scotland, whose collections are now part of National Museums Scotland. With the portrait gallery as the sole occupier, there will be 50 per cent more display space following the redevelopment.

"With the space we have at the moment it is difficult to create a coherent narrative," says Holloway. The gallery is being divided into five key areas: reformation, enlightenment, empire, modernity and contemporary. The displays will be changed frequently around these themes and there will be a wide definition of portraiture, taking in landscapes and the gallery's photography collection.

"It is going to be much more wide-ranging than other portrait galleries," Holloway says. "We have got this programme linking Scottish art, Scottish history, geography and photography, so there will be a very rich diet."

Many people in Scotland do seem supportive of the gallery, and more than 2,000 turned up to oppose its closure when this was threatened in the early 1990s. The public still looks out for the gallery today and Holloway says he is constantly asked: "You are not going to ruin the building, are you?" He says the other major concern is that the cafe's scones will still be available after the redevelopment.

But Holloway is probably as attached to the gallery as anyone, having first joined in 1983 as the deputy keeper. He became its director in 1997, replacing Duncan Thomson, who Holloway is still in touch with.

Holloway, who looks far younger than his 60 years, has spent most of his career at the National Galleries of Scotland, only leaving for a three-year stint at the National Museum of Wales in the early 1980s. He first joined the organisation in 1972, when he became a research assistant at the National Gallery of Scotland.

"The National Galleries was a completely different place when I joined. I have seen it grow in terms of ambition and in the services it provides. The whole climate has changed. We were hardly doing exhibitions in 1972."

Scotland has also move on since Holloway started at the NGS, the most obvious difference being how it is governed. "Devolution has brought us under the Scottish Executive's control, so we see our minister far more than we used to. And they've been brilliant about funding us."

But Holloway also feels that some of the portrait gallery's thunder might have been stolen by the Scottish Parliament. "Before the parliament opened in Edinburgh, the gallery was one of the national symbols - we fly a flag for Scotland, we are about Scottishness. Once you got a parliament, that is another symbol, so you could say that the gallery took a lesser role."

But now the gallery is about to close, Holloway will be working hard to make sure it opens with a bang in 2011. Part of this will come from commissioning new works.

"We don't do as many commissions as we would like because of cost, but we will do a series of really interesting things between now and the opening so that we have a lot of people you would expect to see in the gallery."

Holloway says he has been emboldened by the success of recent commissions. "We did a marvellous portrait of three cancer surgeons. You might think that a lot of people would find that just awful and horrific, but the reaction has been incredibly strong, people understand what it is all about. We thought it was going to be a really difficult picture to sell to the public, but it has been very easy."

For the reopening, the gallery has commissioned Stuart Franklin, a member of the Magnum agency, to produce a series of photographs on farming in Scotland. Holloway has already helped him find a pig farmer in the north east. He will also commission a German photographer to do a series about the Pakistani community in Scotland.

"The reason for Germany is that a couple of years ago I felt we should concentrate on a single country other than Scotland. We have not got the resources to cover the world, but why not one place? Germany is the first one we are looking at. This is an idea I entirely plundered from the BM, who did it with their print collection."

Holloway also has big plans for displaying Scottish painters such as George Jameson and John Lavery. All these projects, combined with a revamped building, should keep him busy for the next few years and he might have done the right thing when he recently got rid of two of his four motorbikes. But he still has a Ducati and a Honda, so will be able to make sure that his obsession for biking does not take a total back seat.

James Holloway at a glance

James Holloway was born in 1948 and graduated from the Courtauld in the early 1970s. His first job was as a research assistant at the National Gallery of Scotland where he stayed from 1972-1980. He then spent three years as the assistant keeper of art at the National Museum of Wales.

Holloway returned to the National Galleries of Scotland in 1983 as the deputy keeper of art at the Scottish National Portrait Gallery. He became its director in 1997 when he replaced Duncan Thomson.

He is a member of the curatorial and conservation committees of the National Trust for Scotland and also serves on the committees for two stately homes, Hopetoun House and Paxton House.