A great big box of books arrives at my house before Christmas. My 15-year-old son stares at them and me. "Are you really going to read them all?" he asks sceptically. For years he has watched me dash chaotically from theatre rehearsals to meetings, and has no memory of me spending tranquil weeks nursing a novel. I unpack the box. Inside are more than 25 books, some still unbound. They are tantalising and thought-provoking. Twenty-five women sat and wrote these works over the past year - each woman taking the plunge, taking the time, holding her nerve until her early ideas matured into a finished piece, which strangers now consider and criticise. I start reading.
Another box of books arrives in January. I gulp like someone who has just eaten five courses and is offered yet another. My 17-year-old daughter - a writer and wrecker of kitchens - looks at me pityingly. "Mum, are you really going to read them all?" She unpacks the box. We scan the names of the authors, known and unknown, and agree that the act of writing is a courageous one. It is my loyalty to artists, as well as a genuine interest in books, that makes me spend time, day after day, reading and making notes for our first judges' meeting.
The judging process is both fun and businesslike thanks to our chair, the broadcaster Jenni Murray. There's no "forming and storming" at the first meeting; there's simply no time for me and my fellow judges - the comedian Jo Brand, newscaster Moira Stewart and writer Joanne Harris - to try to impress each other. Narrowing 50 books down to 20 is pretty consuming. Kate Mosse, co-founder of the Orange Prize, reminds us of the rules. I blink. Yet again my administrative skills have let me down. If only I had opened my letter of instructions, I could have spent more time in rehearsals, meetings and sleep. We select the longlist, which includes very humorous and very stark, poetic work. It reflects our personal tastes, with everything from a novel set in the Victorian sewerage system to one about clairvoyance in a home for the elderly.
I go "off message" for a while to direct On the Town at the Coliseum in London and then The Importance of Being Earnest in Australia. My 20 books go with me, urging me to start the long, hard task of comparing, contrasting and choosing. They keep me company in my hotel room. I am excited by the volume of ideas pouring from these writers. It is not so many years since the female novelist was an exception; an oddity. The Orange Prize has proved that acknowledging the achievement of any group of people leads to confidence and further achievement. Who would now question the role and ability of a female novelist?
Yet the longlist has to be reduced to a shortlist, and that's when things get sticky. Our next meeting is bloodier. Losing a book one is fond of begins to feel like hacking off a limb. Oh, how ruthless that gang of three called "the other judges" can seem. Jenni assuages, checks and calms. And then there are six.
When people have found out I am an Orange Prize judge, they invariably ask: "Do you really have to read all the books?" I am shocked. Do people think the choice of a winner is a casual affair? No, it never is. The final judges' lunch happens just before I, as chair of culture and education for the 2012 Olympic bid, receive the IOC report that puts London neck and neck with Paris. And that's what judging the prize is like. Things are neck and neck, then the wind changes for one judge, we vote and have a winner: Lionel Shriver's We Need To Talk About Kevin, a surprisingly difficult and haunting book among many greats.
So my judging is over, and now I wait to be judged myself, as one of London's Olympic bidding team. If the IOC has read our candidate book, then I'm sure we'll win. But in the end, as with all those women, making a mark for what one believes in is a bigger prize.
Ridiculusmus: the importance of being earnest, directed by Jude Kelly, is at the Barbican Centre, London EC2 (020 7638 8891) until 9 July