"Belle de Jour" is the pseudonym of a woman scientist, blogger and author, known for writing about her experiences as a call girl.

Now that her identity has been revealed, an interview with her appears on Freakonomics:
In 2003, a young American woman in London studying for her PhD. ran into money trouble. To support herself while writing her thesis, she joined an escort service. Under the assumed name Belle de Jour, she started to blog her experiences. That blog led to a series of successful, jaunty memoirs beginning with 2005’s The Intimate Adventures of a London Call Girl. The books were adapted for television in the U.K. (where she is portrayed by Billie Piper) and later in the U.S. All the while, as Belle de Jour garnered more attention — and criticism, for portraying prostitution as a glamorous career choice — the woman behind Belle de Jour struggled to keep her anonymity. This month, as an ex-boyfriend threatened to blow her cover, Belle approached one of her critics, the London journalist India Knight of the Sunday Times, to reveal her identity. That resulted in an article, published Nov. 15, outing her as Dr. Brooke Magnanti, 34, a neurotoxicologist at the Bristol Initiative for Research of Child Health. This week, she agreed to answer a few questions for the Freakonomics blog, about her work as a call girl and as a scientist.
I think a lot more women should be entering this sort of career, it should be a lot more commonplace, the expected quality of service should become higher, prices of high quality service should be driven somewhat lower, and a lot of prejudice should be shed by the public.

We owe a lot of gratitude to women like Dr. Magnanti for helping especially with the latter.

Also, I just love the language she uses on her blog. A couple of quotations:
Reminded me of something we used to say, that inside most porn actresses is a failed real actress*. Inside every tabloid hackette is a not-very-bright girl who dreamed of being Kate Adie but didn't have the work ethic or talent to make it happen. Journalists my sweet Tallahassee ass. You are to historical record what my books are to fine literature.
Go on, open a Sunday supplement today. How many pages in before you encounter some polly filler by a female columnist implying men in general (or her man in particular) doesn't pull his weight at home, while she majestically juggles family, work, and the burden of having a vagina which has the audacity to bleed once a month? How many pages before you encounter some self-flagellating male columnist admitting to same?

Let me state for the record that if being a man was easy, hookers wouldn't exist. Fact.

And this:
He asked me to undress to the level of underwear (requested: bra, stockings with suspenders, knickers over the suspenders - so the stockings could stay on during sex). I did this.

Then, he asked if I would undress him.

And that was when I noticed. The odd angle of his uneven shoulders, his narrow chest, the gouge-like scars. I didn't ask, he offered nothing, and I ran my hands over his body with no hesitation. He asked me to swing his legs onto the bed, and when I did, I saw the walking sticks next to it for the first time.

That client did not reach orgasm but enjoyed the sex. We talked afterwards, he about his upbringing in Africa. His hair was thick and dark and when he said his age I could not believe it. He was much older than he looked, far older than my father! I could see in the moustache and cheekbones a man who, had his health outcome been different, might have been a dashing RAF pilot in some other world. I continued to stroke the unusual topography of his body, lightly over the lumps and odd moles, harder when I reached his (still semi-erect) penis. He, correctly, identified where I was from based on the pronunciation of a single word that came up in conversation. I can't remember if this encounter is in any the books... on the blog, he was mentioned only in passing, and not because of disability. We talked about holidays, about sunshine and the sea.

This is what comes to mind when I read people like Harriet Harman describing selling sex as "truly medieval" and "just so wrong". For her, presumably, her sex drive is constrained neither by opportunity nor the form of her body. She can and, I assume, does have sex as and when (and if) she wants it.

Other people are not in the same position. And surely denying them access the human touch is short-sighted and "truly medieval". I do not believe for a single moment, however, that these campaigners against sex work have a single ounce of compassion for the trafficked women they claim to want to help, so perhaps asking them to have compassion for people who, simply by fate, happen not to have the freedom or opportunity for a fulfilling sex life so many of us take for granted is far too large a request.