Romantic fiction has never had it so good. Mills & Boon publishes 50 new titles a month and as it celebrates its 100th anniversary it is selling a book every five seconds in the UK alone. Not even the combined effects of feminism, celebrity culture, chick lit, falling literacy rates, ladette culture and the run-down state of our libraries have put a dent in the female reader’s appetite for a good dollop of romance.

The stories are translated into 26 languages and sold in about 100 international markets, with at least 1,300 writers pounding the word processor to keep up with demand. The brand is famous (Mills & Boon is in the OED, definition: “romantic story book”) though the authors are almost never household names.

In the 1960s Violet Winspear – an unmarried woman who lived with her mother in Leigh-on-Sea – enjoyed a certain notoriety.

“She had what it took to write torrid, sexy romances,” explains M&B’s marketing director, Clare Somerville. “Her 1970 sheikh novel Tawny Sands set the whole of British womanhood a-tremble.”

M&B is a lot more explicit these days, but it’s still romance, not hot passion, that’s the banker. Gill Sanderson, who has contributed about 40 titles to the “he was a doctor but was he the man for me?” genre, knows what works. “It’s about love: an absolutely universal emotion. Everyone – well, 95% – has experienced it. I think when people read a Mills & Boon they remember what it was like when they first fell in love.”

So although the sexual shenanigans can be quite blush-making, they are, insists the editorial director, Karin Stoecker, “always in a committed relationship”. And that’s the point: “There’s a promise to the reader that there will be a satisfactory ending” to the 55,000 or so words for about £2.99. This comes despite – invariably – the hero’s arrogance, the heroine’s reluctance to open herself to the full flowering of true passion, and sundry other obstacles including amnesia, erroneous marriage to the wrong person, and “the other woman – the scheming, nasty, conniving one who gets done down on about page 94”, according to Sanderson, who is not, however, an entirely typical Mills & Boon author.

“She” is “just under 15 stone, broad-shouldered, big-chested, with a moustache but not much hair”. In fact Gill is actually Roger, the lone male in the firm’s roster of writers. By his own description, the sixtysomething former college lecturer from Liverpool hardly lives up to the physical ideal of hard-bodied, craggy-jawed M&B man, but surely he’s as loaded as they are (billionaire, millionaire and doctor seem to be the genre’s three acceptable income levels). Yet though he’s sold nearly 2m books – translated into 17 languages – he tells me he is certainly not rich, just “comfortable”.

Sanderson (Gill is his wife’s name; they’ve been happily married for 32 years) submitted hospital romances to M&B for three years before it accepted one. “It’s a skill you have to learn,” he says.

His readers are aged 12 to 90. “There doesn’t appear to be any limit as to intelligence: I know university students who read Mills & Boon,” he says. Even the late Benazir Bhutto was a fan.

To retreat into a world where heroines never get horribly drunk or have abortions or one-night stands, but instead find ultimate fulfilment in the strong arms of a very rich man – no wonder the sterner feminist commentators condemn M&B as character-weakening escapism.

What’s wrong with that, asks Sanderson. “Mills & Boon readers know what love is like and have an idealised view of what it should be like – I cater to that. So if that’s escapism, then yes. I want them to go away happy.”

Explore Books

• Book Extracts

• Book Reviews

• Books Group

• Audio Books

Times Recommends

• Superfreakonomics by Steven D Levitt and Stephen J Dubner
• The Times picks the 50 best paperbacks of 2009
• Vincent van Gogh’s letters show the soul of the artist