It's a bit like writing a new novel every year,” says Diana Reich, of programming the Charleston Festival. “There are a lot of blank pages and I always panic and wonder what I am going to put on them that will compete with the previous year.”

Her anxiety is understandable. In its 20-year history, the respected Sussex literary festival has attracted some of the biggest names in their field to perform in new and innovative ways. Diana, the festival’s artistic director, recalls Harold Pinter reading his own work – the first time he had agreed to do so at a festival. “It was mesmerising. It made me understand his writing in a way I hadn’t understood it before.”

She also has fond memories of Iris Murdoch, who would only agree to appearing if she was guaranteed a trip to the seaside. “She came to Charleston twice, despite refusing most invitations, and part of the deal was that we would take her to the sea where she would paddle and sometimes immerse herself in the water, despite the fact she never had a bathing suit with her. You can imagine what that meant!”

This year’s event has the added pressure of being the 20th anniversary of the literary festival, held in a large marquee in the garden of Charleston, one-time home of Bloomsbury painters Vanessa Bell and Duncan Grant.

“Twenty years ago, the Hay (literary) Festival was only two years old and the only other two festivals of significance were Cheltenham and Edinburgh, so there wasn’t a real frame of reference. We started from scratch and went from one year to the next, never knowing if we’d pull it off.”

In celebration of the milestone, the festival welcomes more high-profile names than ever before (among them, Graham Swift, AS Byatt and Jeanette Winterston) and there is a focus on events that relate to the context of Charleston itself.

Publishers Faber & Faber will run a series of “master classes” for writers both established and aspiring and a number of the talks have an art bent. A fitting marking, then, of two decades of creative history.

“Sometimes it feels unbelievable that it’s happened so quickly,” says Diana of the past 20 years, “but on the other hand it also seems incredible that we’ve managed it so many times. I hope for the future we continue to have an element of unpredictability. We aim to be unpredictable and unique and encouraging of new ideas.”

Here, Diana picks out some highlights of this year’s programme.

Times and ticket prices vary. Visit www.charleston.org.uk/charlestonfestival or call Brighton Dome box office on 01273 709709.

Voyages Into The Mind: Hilary Mantel and Ann Wroe, May 15, 6pm

A discussion on how far one can push literary boundaries by inhabiting the minds of historical characters and revered writers from the past. Hilary Mantel has just published Wolf Hall, a novel that takes readers behind the scenes at the court of Henry VIII, while Ann Wroe’s biography, Being Shelley, was hailed for abandoning the usual conventions of the genre. “Anyone interested in literary fiction on an historical topic should find this a very exciting event,” says Diana.

Maynard Keynes: A Man For All Seasons, with Vince Cable, Will Hutton and Robert Skidelsky May 16, 2.30pm

As the current economic crisis continues, the life, legacy and contemporary relevance of Bloomsbury economist Maynard Keynes is examined by a panel that includes Lib Dem economic spokesman Vince Cable, author and broadcaster Will Hutton and Keynes biographer Robert Skidelsky. “To get these three together in the current climate will be very stimulating and exciting – possibly even ground- breaking.”

Art And Authenticity: William Feaver and Deborah Moggach May 17, 7.30pm

“Here we have two authors who have been involved with work that has made a huge impact over the past few months,” explains Diana.

The National Theatre’s play The Pitman Painters was based on William Feaver’s book, which tells the story of a group of miners at Ashington Colliery who became artists in the inter-war years, while Deborah Moggach’s adaptation of The Diary Of Anne Frank – starring Tamsin Greig as Frank’s mother – was acclaimed when it showed on BBC One last year.

“They have both translated works of art into new media and I was very interested in getting them together talking about how they tackled it.”

Into The Frame: Julia Neuberger, Colm Toibin and Andrew Motion May 20, 6pm

“It's going to be a bit like Desert Island Discs but about paintings,” Diana says of this event, which asks its guests to discuss paintings of significance to them.

Against projections of their chosen works of art, the guests will discuss why their chosen two paintings captured their imagination and what they mean to them.

Darwin: Steve Jones and Ruth Padel May 22, 6pm

Aside from the media focus on Charles Darwin this year, the bicentenary of his birth, the revered geneticist and evolutionary biologist has a special significance at Charleston.

“Sir Lesley Stephen (father of Bloomsbury Group stalwarts Vanessa Bell and Virginia Woolf) was a friend of Darwin’s and that friendship percolated through the families. There are strong links between Darwin and his family and the original inhabitants of Charleston.”