With her latest novel, Northern Irish writer Deirdre Maddenreturns to the theme of mutable identity. She tells Sorcha Hamilton about finding her own voice

DEIRDRE MADDEN SPEAKS in a soft, almost hushed Northern accent. She likes to stand back, it seems, and allow her work to take centre stage. "I'm not really interested in talking about myself," she explains. "It's the work that matters."

It's a warm, humid day, but the hotel staff, distrusting of the Irish summer perhaps, have lit a fire. Madden says she loves the smell of turf, and I'm reminded of a line in one of her books about "a cottage in Gillnacurry with a fire blazing in the grate and a plate of apple crumble and fresh cream in your hand".

Madden is regarded as a pivotal voice in Northern Irish writing, her understated yet complex fictions often touching on the religious and political turmoil of the North. She has received numerous awards - the Hennessy award, the Rooney Prize and the Somerset Maugham award for her second novel, The Birds of Innocent Woods- and has written two books for children. She teaches literature and creative writing in Trinity College and has just finished her latest, and "most difficult", novel.

Molly Fox's Birthdayis a thought-provoking read, Madden returning to themes of friendship, identity and the complexities of the creative process. Set in Dublin, it follows the musings and memories of a playwright staying in the house of her friend, the actor Molly Fox.

By blurring the lines between real life and acting, the book suggests that we are all actors in one way or another. While the character Molly is admired for her powerful performances, her presence off the stage is at one point described as "curiously unimpressive". Her old friend Andrew, on the other hand, has reinvented himself as a scholar in London, leaving behind the Troubles of his Northern background.

This remaking and escaping the past is a recurring trait in many of Madden's characters. In her earlier novel, One by One in the Darkness- which was shortlisted for the Orange prize - one of the sisters changes the spelling of her name and leaves her rural family home to work in a fast-paced fashion magazine in London.

"Some people are very unhappy with who they are when they start out," Madden says. "they make a conscious decision, like Gatsby, to change - like their accent or name. Sometimes it seems phoney or affected, but a few people can be much the better for it."

It's a topic Madden feels strongly about, and she's determined to get the point across clearly. "Sometimes a person isn't who they need to be, so they make a decision to change. They hate their background so they move to another country and become something they were more intended to be."

Exactly how much we know about our friends or family has always been a curiosity to Madden. Although we live in a more confessional type of society now, she says, where people tell each other a lot about themselves, "you do always wonder how much you really know about the people in your life".

This is explored in Molly Fox's Birthday, where the narrator confesses how she chose not to tell Molly Fox about the night she slept with Andrew. "The book is very much about identity," Madden says, "how people can behave differently - one way with their family and totally different with friends."

LIKE HER PREVIOUS novel Authenticity, which examined the lives of artists, Madden's latest book unpicks some of the complexities around the creative process. At one point the narrator wonders if acting is "psychologically dangerous". Does the same apply to writing?

"Maybe the arts are a bit more dangerous than people realise - you can be engaging in something that is very destabilising to yourself - it can turn sour." But it's an uncomfortable, slightly delicate topic, Madden says. She pauses, intently focused: "I think writing can be psychologically helpful, it can help you make sense of things and get to grips with things," she says. "It's a hard thing to talk about."

The vocational nature of art is an important concept for Madden. "Some people just should be doing something creative," she says. "It doesn't necessarily mean that they must be very good at it - but it's more that that's what they should be doing, it's what they need to do."

From an early age, Madden was drawn to books and writing. She was first published by David Marcus, then literary editor of the Irish Press and a keen enthusiast of the Irish short story. "My mother always bought me lots of books when I was child, and both my parents really encouraged me," she says.

Madden laments the way society now seems to discourage people who express a desire to work in the arts. While many parents will send their kids off to dance and acting classes, they are terrified if their children later want to pursue these fields, she says. "I don't know what it is, but something in this world, or society, damps down that type of creativity the older you get."

Molly Fox's Birthdaywas one of Madden's most challenging books to write. While she looked to Mrs Dalloway by Virginia Woolf as a structural model, the one-day form was difficult. "Interweaving the memories and the sort of trivial things that the narrator does on the day without feeling as if you've gone off on a tangent was difficult," she says.

But did she enjoy writing it?

"No, I really found this a difficult book to write and enjoyed it much less than Authenticity. I learnt a lot technically from it but I was so relieved when I finished it."

THE HIDDEN DRAMA of life is also a theme in Madden's work. The Troubles, while not always forming the central plot, often hang ominously in the backdrop. There are stories or memories of violence, which characters often struggle to come to terms with. In Molly Fox's Birthday, Andrew desperately tries to understand and grieve for the murdered brother that he once despised.

"I think we've barely started to understand how terrible the Troubles were - we have an awful lot ahead of us," says Madden. How we remember this past is critical for Madden and is particularly evident in Molly Fox's Birthday when Andrew is faced with his own son's questions about the unspoken violent death in the family.

Madden examines a changing Ireland with a delicate yet sure touch. How we respond to the different types of role-playing in society is central to these adjustments. Religion and the responsibility of the priest, for example, form a gently provocative thread throughout her latest book. The narrator has a confused relationship with her Catholic upbringing. She rejects it, yet sometimes finds comfort in its familiarity, or the recital of prayers at Mass. When she describes how her brother Tom, a priest, came to visit in London, the narrator remembers how embarrassed she felt, riding around on the Tube with him in full religious garb. When her close friend Molly begins to confide in Tom, she feels even more uncomfortable.

"I was interested in looking at religion in modern context," says Madden.

Getting away from the negative stereotype of the priest, she says, was key to this. In the book, Tom describes how he was woken up in the middle of the night to go to the scene of a horrific traffic accident, where a young girl had died.

"There's been a lot of bad things around the church, but there are a lot of really great priests out there, and often they have a lonely, hard life. So what I wanted to do was to explore how people might relate to that."

The bustling family home, with its open fires and hearty dinners, provides a source of warmth in Madden's novels, despite the Troubles often looming in the background. And often it's the objects - the photos in the hallway or the polka-dot mug in Molly's kitchen - that are just as telling as the characters and their affairs or secrets of the past.

But many of Madden's characters have an inability to recreate this warmth in their own apartments or houses, after they leave the family home. Like the narrator in Molly Fox's Birthday, often home is just a place to crash - suggestive, perhaps, of some greater absence. While Madden herself has lived away from her native Antrim for many years - in France, Italy and now Dublin - creating a sense of home is no small issue. "It's always been very important to me to make a home. It doesn't have to be grand, just lived in," she says. "And I'll always have flowers."

Deirdre Madden will be at the Kilkenny Arts Festival on Aug 9. In Books tomorrow, Bernard O'Donoghue reviews Molly Fox's Birthday