Barry held in his hands a plain package, just another manuscript from yet another aspiring children's author. He wasn't keen on the title and he couldn't quite get his head around the rules of a strange game that featured within its pages, but still there was something that felt good about it.
It was Barry's first meeting with Harry. And the words he uttered next to the nervous young writer in his London offices have gone down in publishing history.
"I did say to her that she would never make any money from her book," he says, unable to keep the smile from his voice. "But I said it out of the sheer goodness of my heart, honestly! The truth is I was worried about her.
"Here was a single mum and the amount of money I was paying for these books wasn't going to pay the bills for long - a few thousands. Look, not many children's hardbacks sold in those days.
"Of course what I should have said was: 'OK, I'LL never make any money out of children's books but you, yes you, on the other hand will make more than anyone else in the entire universe'."
And hasn't she just. When a grateful JK Rowling settled down in Barry's office at Bloomsbury Children's Books that late summer day in 1996 to sign up for a fee of just a couple of thousand pounds, no-one, certainly not any of the publishers who had already sent her packing, could have guessed at how dramatic the impact of her first Harry Potter book might be.
"If it wasn't for Barry Cunningham, Harry Potter might still be languishing in his cupboard under the stairs," JK Rowling has admitted.
For her it has, of course, been an exceptional multi-million-pound, best-selling journey which has seen her series of books about a heroic young wizard take the publishing world by storm. For millions of dedicated readers, Harry's adventures have become almost all-consuming.
And for Barry, the son of a hardworking Leith serviceman, well he's never been able to live down the fact that he once told JK Rowling that she might, perhaps, want to think about a day job.
Nine years on, he admits the arrival of a new Potter tome earlier this summer meant another frantic episode of fending off calls from people who want to meet the man who both "discovered" JK and who offered her such unnecessary financial advice. "I'm the man they come to when they can't get to Jo," he laughs. "Which is why I did the Oprah Winfrey show just after the latest book was launched. It does all get a bit silly. I start to dread every time there's a new Harry Potter book on the way."
Barry is now regarded as one of the country's leading figures in children's fiction despite never having written a children's book. Instead he draws on a lifelong love of books that began when as a boy he settled down in bed in his parents' home to read the opening pages of Treasure Island and found himself transported to the Admiral Benbow inn.
Perhaps he needed an escape route from reality more than most. Barry was just six years old when his father, George, died from lung cancer. "My dad came from Leith," recalls Barry, who now runs a highly successful children's book company, Chicken House, based in Somerset.
"He left when he was young and joined the Army where he became an engineer. He had cancer - he smoked like a chimney, he always had a cigarette hanging from his top lip. It was like that in the 30s and 40s, they were told smoking was a healthy thing to do. He was just 44."
Barry retains a strong link with his father's Leith family - "There are hundreds," he laughs. "My father had a lot of relations." And the fact that JK Rowling, the writer he discovered, has now made her home in Edinburgh, not far from the Cunningham clan, does strike him as slightly ironic.
There's that, plus the fact that both of them seem to have an uncanny knack of knowing just what children want from a book.
"I always loved books as a child," shrugs Barry, who recently sold Chicken House to one of the biggest children's book publishers, Scholastic. "I loved running away in my imagination. My biggest moment as a little boy was in those days you got a different coloured ticket when you went to the library and took books out of the adults' section."
So he plunged into the world of publishing, working in marketing alongside the writer he rates as the greatest of all children's novelists, Roald Dahl - even if Barry once commented that the author "didn't like children". He also worked with Spike Milligan and Quentin Blake and dozens more, helping to shape his ability to spot what might make a best-selling children's book.
"It was my experiences with Roald Dahl and my own kids - I have six - that helped me understand more about what children want from a book," he explains. "There's a big difference between the books you are told to read and the book they hug to their chests and want to keep forever. They almost put them under their pillow, it's that personal thing that kids get from certain books."
It was while working in Bloomsbury's newly created role of commissioning editor for children's books that Barry met Harry - or, at least, his creator.
"I just got the brown envelope one day," he says. "Ha! If only I had known then what I know now! I just read the famous Harry in one night and I knew. It wasn't that a finger came down and a voice declared that this book would change children's books forever.
"I just sat there in my office and tried to understand the rules of quidditch. And I thought Harry Potter and the Philosopher's Stone was a silly title. But I loved the story and the heroism, I liked the friendship between the three main characters, the owls and magic was great.
"And I was sympathetic for the characters, so I bought the first two books in a deal that was negotiated in five minutes. The first thing she said was: 'How do you feel about sequels?'. So then she told me and I was amazed she had it all worked in her mind. To have him grow up was really radical because in those days in most children's sequels the same thing happened again, then again and then again. But to have him grow up and change and deal with threats from dark forces, that's something different and Jo has really taken the audience with her. The success is mostly down to the quality of the imagination."
He may have discovered JK, but even he didn't have an inkling that Pottermania would crash through so many boundaries. "When we published the first Harry Potter they were saying boys had problems finishing the back of a PlayStation packet never mind a 600-page book, now kids fight to finish them.
"What it has done for reading and making books cool again is astonishing. I'm really proud of what she went on to do."
Indeed, he places Rowling in his personal top five of children's authors - alongside Dahl, CS Lewis, Phillip Pullman and Enid Blyton - and regards her as probably the best children's writer this century. And as for the next JK, he points to Cornelia Funke, one of his own Chicken House authors who, he says, is "absolutely the next big thing".
So with such a strong background in children's books, does Barry ever see himself earning millions from a children's classic?
"I work with so many people that I could never have an original voice in my head," he protests with a chuckle. "That said, I'm 52 but I've kept the child within me - most successful children's authors are children at heart. Who knows, maybe one day I will go to the back of the wardrobe myself."
FROM ELVIS TO CHAPLIN, STARS WHO GOT THE KISS OFF
BARRY CUNNINGHAM is not the only person who has told someone talented that they might not make it big - but at least he still signed JK Rowling. Others weren't so blessed with foresight...
Charlie Chaplin was initially rejected by Hollywood studio chiefs because his slapstick miming was considered "nonsense".
After Fred Astaire's first screen test, the memo from the testing director of MGM, dated 1933, read: "Can't act. Can't sing. Slightly bald. Can dance a little." Astaire kept that memo over the fireplace in his Beverly Hills home.
After his first audition, Sidney Poitier was told by the casting director: "Why don't you stop wasting people's time and go out and become a dishwasher or something?"
In 1944, Emmeline Snively, director of the Blue Book Modeling Agency, told modelling hopeful Norma Jean Baker: "You'd better learn secretarial work or else get married." She, of course, became Marilyn Monroe.
In 1954, Jimmy Denny, manager of the Grand Ole Opry, fired Elvis Presley after one performance. He told Presley: "You ain't goin' nowhere, son. You ought to go back to drivin' a truck."
Decca Records turned down a recording contract with the Beatles, below, with the evaluation: "We don't like their sound. Guitar groups are on their way out."
When the Bell telephone company was struggling to get started, its owners offered all their rights to Western Union for $100,000. The offer was disdainfully rejected with the pronouncement: "What use could this company make of an electrical toy."
Stan Smith was rejected as a ball boy for a Davis Cup tennis match because he was "too clumsy". He went on to win Wimbledon, the US Open and eight Davis Cups.
Walt Disney was fired by a newspaper editor because "he lacked imagination and had no good ideas".