I write when life is calm, and that means when my kids - William, 14, Eames, 11, and Patrick, 6, - are in school, between 9 a.m. and 3 p.m. Having children has made me efficient, because I know that at 3 p.m., I really do have to stop writing and go collect them. Occasionally I do some work late at night, after they have gone to bed. It's a good time to read over what I've written earlier in the day with a fresh eye. The nice thing about working at night is that I can keep going if I want - I don't have to sleep, whereas I do have to pick up the kids.
People acknowledge now that I write between 9 a.m. and 3 p.m. so my friends and family don't call. I learned through trial and error when I started writing that I would have to shut the door. This isn't easy - as a woman I grew up with the idea that other peoples' needs are more important than mine. I had fun talking to Nuala Ni Dhomhnaill about this recently, on my trip to Ireland for the Aran Islands International Poetry and Prose Festival. She told me about sitting in her room and writing a poem, listening to her kids downstairs, murdering each other. And thinking, I should go down to them. But not yet.
One day a week I teach a creative writing course at Johns Hopkins University at Baltimore, and at the weekends I don't write; I prefer to catch up on my reading.
Sometimes I get stuck during the writing of a novel, so I've gotten into the habit of working on two novels at once. Even with a short novel, you spend a long time with these characters and sometimes you get weary of them and your ambitions for them. If I get a block with one, I move to the other. It gives me an out, a way of procrastinating instead of getting up and cleaning the house.
I never do any research until I have written the novel. Otherwise I would waste hours in the library looking up facts and figures. Charming Billy is about an Irish-American alcoholic, so after I had written it I read a lot of first person accounts by alcoholics, and some histories of the second World War, to confirm that what I had written had the ring of truth. The book is mostly based on a lot of experiences I've heard of, coming from an Irish background myself - all four of my grandparents were from different parts of Ireland, and met in New York.
When I'm drafting something new, I have a ritual: I use a blue Bic pen and a yellow legal pad. There are writers whose books I like to keep near me, whose work reminds me why I'm doing this. Vladimir Nabokov sees his characters so keenly - they always have a real heart beating in them no matter how despicable they are. Virginia Woolf, Wallace Stevens, the American poet Donald Justice: all use language in an inspiring way. I love Yeats and Heaney too.
My husband is a neuroscientist and commutes to Philadelphia (we live in Bethesda, Maryland, outside Washington DC). He stays in Philadelphia a couple of nights a week, so my evenings are busy with the children and their homework. Although we work in different fields, my husband's approach is actually quite similar to mine. We both start off with an idea and go about proving or disproving it. Our activities are self-generated and tied up with ego in peculiar ways that we recognise. I prefer to listen to him talk about his work, though, because when it comes to mine, I am so often discouraged. I'm always groping in the dark trying to attain some ideal, and most of the time I feel I'm not quite there.
We've really enjoyed coming back to Ireland: we were in Ireland for our honeymoon 20 years ago and it has changed a lot: so much prosperity, new homes being built; the economy is booming. It's wonderful to see.
Charming Billy, winner of the 1998 National Book Award in the US, has just been published on this side of the Atlantic by Bloomsbury at £15.99 in the UK