Second-hand book shops should be paradise for bibliophiles, but many are struggling to survive in these affluent times. Anna Carey looks at how the successful ones stay open

'It's just something I have to do," says Adrian Connolly. "If it means rescuing things and looking after them, well, so be it. I have no power to withstand the pressure of this duty. I just have to carry it out." Connolly is not a doctor or a teacher or even a priest. He runs a second-hand book shop, Connolly's, in Cork. And those who appreciate the magic of a really good second-hand book emporium will understand what he means. A good second-hand book shop isn't just a shop. It's a place of serendipity. It's a place where books are cherished, where new discoveries are made and old favourites refound. It's a place where a book lover can wander for hours on end.

But these literary paradises are not as common as they once were. There are still antiquarian book shops for serious collectors, but if you're looking for a paperback copy of Brideshead Revisited rather than a first edition of Ulysses the choice is alarmingly small. There's no real Irish equivalent to New York's magnificent Strand. The quays, once Dublin's version of Charing Cross Road, are almost bookshop free. So does affluent Ireland still want to read second-hand books?

Booksellers give conflicting reports. Some say business is better than ever. "We've had to expand the premises," says Emily O'Flaherty of Galway's excellent Charlie Byrne's. "Our storage warehouse is now open to the public too. We're constantly restocking." Chapters in Dublin also reports that business is booming. "It's noticeably increased over the last few years," says Colm McDonagh, its manager.

But others say the trade is dying. In the past 10 years most of Dublin's second-hand book shops have closed their doors. The long-established Dandelion Books, on Aungier Street, which shut down at the end of last month, is the latest casualty. The second-hand book trade isn't being killed by a lack of readers: the weekly outdoor book market in Temple Bar does good business. But the traders have no overhead costs besides their barrows. For shops, spiralling rents and time-strapped customers can bring a business down.

"What's killing the second-hand book trade is rent," says Pádraig Ó Mealoid, the former manager of Dandelion Books, who set up his own second-hand shop, the short-lived Flying Pig, in 1997. "It's killing a lot of independent businesses. Most second-hand book shops are in rented premises, and when landlords put the rent up the shopkeepers often just can't afford to pay it. Only chain stores and high-end businesses can afford city rents these days."

His former colleague Rory Lennon, who has been forced to shut down Dandelion after two years of declining profits, agrees. "I know one book seller who's had to move in to his shop because he couldn't afford to rent both it and his flat. He just keeps a camp bed in the shop."

The fast pace of the modern world is another factor in the decline of many book shops. Customers often go to second-hand book shops just to browse, to see what long-lost literary treasures they can unearth. And browsing takes time, which people no longer seem to have. "People used to spend entire days in book shops, as if it were a treasure trove," says Adrian Connolly. As book shops rely heavily on passing trade, a busy location is also important.

Some book shops say that Ireland's increased wealth has increased their business. "More people are well educated, and their appetite for reading has increased," says Colm McDonagh of Chapters. Emily O'Flaherty agrees. But other book sellers say that a booming economy has done them more harm than good. "You need more people on the dole to keep the second-hand book trade going," says Rory Lennon. "In our best days about 50 per cent of our customers were on the dole." Connolly wouldn't go that far but believes that when people have more money they generally won't bother looking for a book second hand. "When the economy does well, and people can afford to get a book new, they will."

Of course, not all second-hand book shops are worth saving. Some die because they're dirty, messy and uninviting. And, most of all, because their owners aren't selective when it comes to acquiring books. Some shops might as well have a sign on the door saying: "You won't find anything you like here. And if you do, it'll smell of old cats."

Padraig Ó Mealoid believes book sellers should be more ruthless. "There are book shops that look like everything just came out of a skip. There's no quality control there: they won't discipline their stock, they just think all old books are worthwhile. And they're just not. The idea of an untidy old book shop filled with piles of books is good if those books are all clean 1950s Penguins but not if they're just manky old books that no one will ever want to read. You have to know your customers and know what they want."

Knowing one's customers is important to Charlie Byrne's. "People can bring back their books and get credit to buy more," says O'Flaherty. "It really brings people back to the shops and keeps the books in circulation." The shop also caters to its customers' needs with a "wants book".

"If someone's been trying to track down a book for years - maybe something they remember from their childhood - we'll put it down in our 'wants book' and take their details," says O'Flaherty. "And if we come across a copy of the book we'll let the customer know. It's interesting to see what people are looking for. George Orwell is always on the list: Nineteen Eighty-four never stays on the shelves for long." Other big second-hand sellers in shops all over the country include Jack Kerouac, Michael Moore and Marian Keyes. The worst sellers, according to Chapters, are dated Cold War thrillers. Hardbacks, even new ones, don't sell either.

As publishing moves faster and faster, second-hand shops are often the only way to find certain titles, even relatively recent ones. "As storage is a problem for publishers they tend to give a book six months, and if it doesn't do well it's remaindered," says Connolly. "It doesn't matter who it's by: out it goes from the bookshops. And readers suddenly find that they can't find a book which was just published a few months ago. So they come to me."

There are other advantages to good second-hand shops, of course: apart from the fun of browsing, they make the ownership of literature accessible to people who can't afford new paperbacks. They allow readers to take risks with authors they've never read before. But low prices don't always make the profits necessary to keep a business going in these expensive times.

The future of the second-hand book trade may be online, where overhead costs are just the price of an Internet connection. Sites such as www.abe books.co.uk and www.alibris.com allow book lovers to search for just about anything, from book shops all over the world. Charlie Byrne's sells through www.abebooks.co.uk and its own site, www.charliebyrne.com; O'Flaherty says the Internet has hugely increased the shop's customer base.

But although the Internet can be a wonderful way of getting everything from long-lost Puffins to out-of-print Virago Modern Classics, it can't compete with the thrill of gazing at a row of orange spines and suddenly seeing the title of a much-loved book you thought you'd never see again or the joy of finding an Antonia Forest novel in a pile of old children's paperbacks. But, Connolly says ruefully, "some people have no notion of the romance of a second-hand book shop".

Let's hope such apathy doesn't eventually kill the romance for everyone else.