But when Netflix converted it to a strangely compelling reality show, in which Kondo applies her life-changing magic to the homes of various US hoarders (a sort of supernanny for tidying up), her fame went up a few notches.
Since it hit our screens at the start of January, the world has been thrown into Kondo-mania.
The idea is that you reappraise each item in your house and determine if it "sparks" joy, or is useful. If so, you store it in its place. If not, you thank it (yes, really) and send it on its way.
As viewers of Tidying Up With Marie Kondo will know, there is also a certain amount of folding involved, in Kondo's signature technique. Once free of clutter, your life will apparently be transformed and you will make better decisions.
But the woman herself - who speaks only a little English and relies on a translator - is something of a mystery. Who is this person taking over our homes? And how did she become the saviour of a shopaholic civilisation that worships at the altar of consumerism?
It would be easy to dismiss her as a clever marketing creation - and there is, of course, clever marketing behind her. But as far it's possible to tell, she has lived and breathed tidying her entire life.
Kondo is the second of three children (she has an older brother and younger sister), born to a Tokyo couple - her father was a doctor and her mother a housewife. When Kondo was five, growing up in the waterfront neighbourhood of Koto, she would flick through her mother's magazines in search of good housekeeping techniques.
"Cleaning, washing, sewing - I could do it," she has said. "The only thing I couldn't do was tidying up."While other children at school were in the playground, little Kondo would rearrange the bookshelves. When her parents were out, she would clean; the kitchen would be bleached.
But the young Kondo had to overcome a challenge to become who she is today. She was fixated on what she could throw away, scouring the house with a bin bag in hand. Her parents eventually banned her from tidying. Then came an epiphany, one day after school, when Kondo was 16.
"I looked at my room and felt that I wanted to throw out everything in it," she has explained. "That was the climax of my stress, and at that moment I collapsed unconscious."
Two hours passed before she regained consciousness.
"In my mind came the words, 'Look at things more carefully'. I don't know if it was an actual voice, or a feeling that came from myself. I believe it was the god of tidying," she told an interviewer.
Kondo had divined that, instead of seeking items to discard, she should find what she wanted to hold on to. Thus, the KonMari method was born.
Her 18th birthday was spent in Japan's national library, knee-deep in books about decluttering. The same year, she got a part-time job as an attendant "maiden" at a Shinto shrine.
At 19, Kondo was ready to turn her passion into yen, setting up her own tidying consultancy business, while studying sociology at Tokyo Woman's Christian University. Her thesis, incidentally, was called "How to declutter your apartment."
The business did well, and it was reportedly at her clients' behest that she wrote the book that was to transform her life. Her proposal won first prize in a publishing training course called "How to write bestsellers that will be loved for 10 years."
One version of the story suggests that, at this point, Kondo had not actually written a word. But one of the judges of the prize, Tomohiro Takahashi - an editor at Sunmark, which would become her publisher - has said he "felt a mysterious energy around her", and knew Kondo was going to be famous. He has been vindicated by sales of the book. Kondo has professed herself surprised.
"My publisher warned me that it's rare for a Japanese bestseller to become a bestseller overseas, particularly in America. But it's difficult to say what has changed, really."
It is a typically understated remark from a woman who has tapped into a basic human craving for order in a chaotic world and, with her manager-husband, has turned it into a fortune.
Takumi Kawahara was Marie's university boyfriend. They married in 2012, when he still worked in sales and marketing. But as his wife's career took off, he reportedly quit his corporate job and now works to secure her book deals, and behind the scenes on the Netflix show.
In the corporate filings of the company they set up in 2015, KonMari Media Inc, he is listed as "chief executive". He has also helped build her brand by taking photos for Kondo's Instagram feed; a collection of aspirational images of tidy drawers and wardrobes, interspersed with the couple's two young daughters, Satsuki and Miko, aged three and two (they have already been taught how to fold).
They've accrued 1.9 million followers, some of whom respond to the posts with almost religious euphoria. As for official disciples, Kondo has 215 worldwide. They are known as KonMari consultants, and you can pay them to "Kondo" your home.
Only by following a seven-step process, which includes submitting photographic evidence and putting Kondo's teachings into practice, can someone become a consultant.
There is also a compulsory two-day seminar, which costs $3519 in London or $3226 in New York; practice sessions and an online exam. Qualified consultants can charge what they like and keep all their earnings. They must, however, pay an annual $733 membership fee to KonMari Media Inc.
Aline Lau, 38, the first European consultant, met Kondo at a seminar in New York. "She was very sweet," she says. "Everyone was really excited to see her."
"She's like a little fairy," says Jenny Hayes, a British-based consultant. "You can tell by the way she moves, she's very delicate and precise."
Kondo and her family now live in Los Angeles, where they moved last year. The business is listed at a gleaming office block just north of Palo Alto, but Kondo works from a Spanish-style Twenties home in West Hollywood.
Employees at KonMari Inc describe the firm as a "wellness company", tapping into another modern preoccupation.
According to local sources, Kondo isn't seen out and about much, apart from at book signings and speaking events. "I was always more comfortable talking to objects than people," she once said.
In Japan, some are bemused by her success. She is perhaps not the superstar there, that many perceive her as here.
And her family have tended to remain in the background. Her brother reportedly still lives with his parents and none of them are thought to be involved in the project.
The seeds of it grew within Kondo herself, whose whole life has been devoted to tidying. "And to explaining how to tidy," she has said, "to a very extreme degree."
- Additional reporting by Danielle Demetriou and Josh Boswell
