"Waity Katie" waits no more. The schoolgirl who once hung posters of Prince William in his polo gear on her wall is now set to marry that very prince, and become the first commoner in more than 350 years to marry an heir presumptive to the throne.

Along with the wardrobe questions and a scarcity of wedding invites for regular folk, one key question remains: how did a regular -- if quite attractive and stylish -- young woman manage to snag one of the most eligible bachelors on the planet?

Though wealthy, Catherine Elizabeth Middleton is hardly an aristocrat of storied lineage. She is the daughter of a former flight attendant and former flight dispatcher. Her parents became millionaires when Kate was still young, after they started up Party Pieces, a mail-order (and later, Internet-based) party supplies firm.

Kate grew up in an upper middle class home and was sent to private school, notably the prestigious Marlborough College. She is said to have been popular there, excelling in both academics and sports such as field hockey and tennis, while earning a reputation as a kind and down-to-earth girl.

It is said that when it was time to choose a university, Kate's mother, Carole, encouraged her daughter to nix her first choice in favour of St. Andrew's College in Scotland, where Prince William was due to attend.

Kate agreed and soon struck up a friendship with the prince at the St Salvator's student residence, where they socialized together and played tennis. The public first learned of Kate in 2002, when she was identified as one of three friends with whom William was to share a house for his second year of study.

When they moved in together, Kate was dating another student. But, in a moment soon to become legendary among royal watchers, Prince William's feelings changed on the night that his statuesque roommate agreed to model in a charity fashion show.

Seeing Kate in little more than black underwear and a see-through dress, the prince, who had paid for a front-row seat, reportedly turned to his friend at the show to note "Wow, Kate's hot!"

A fiery romance quietly blossomed among the 21-year-olds. And while they tried to keep their romance secret for as long as they could, by March, 2004, the jig was up, when the two were photographed on the slopes of the posh Swiss ski resort Klosters.

Increased fame, increased pressure

That sent the paparazzi into a feeding frenzy that has let up little for Kate ever since.

Unlike Lady Diana before her, Middleton has handled the press attention as well as she can, showing patience with the paparazzi, offering them occasional smiles and quiet "girl-next-door" glances.

Royal biographer Ingrid Seward said Diana "would be delighted" at William's choice, because she once told her son that the most important attribute in a future wife would be that she is a great friend, which he will need when he becomes king.

"I think any mother would be delighted to have a daughter-in-law like Kate Middleton," Seward told CTV News Channel in an interview from London recently. "She's very serene, she's very dignified, she's graceful, and she looks after William -- she's a brilliant cook. She is really, the mother and the lover rolled into one, and William obviously needs that."

Over the eight years of romance, Kate has made few missteps, giving the tabloids little fodder for gossip.

Recently, there have been tabloid accusations that an apparent pre-wedding diet has turned Kate from sporty and sprightly to gaunt. But overall, Kate has handled the spotlight with aplomb.

If anything, the worst criticism levelled at Kate, who barely drinks and never smokes, is that she has never held down a steady job.

Still, with new-found fame, however, came challenges. In 2005, her lawyers publicly scolded newspaper editors about harassment. Not long after, it was reported that a security detail had been assigned to her watch.

And in 2007, the athletic Kate was forced to pull-out of a charity boat race across the English Channel because of safety concerns.

Meanwhile, after leaving university, Kate was said to have been keen to set up a children's clothing business. And in November 2006, she joined fashion chain Jigsaw as an accessories buyer. But a year later, she left her job to work for her parents' business.

Yet her interest in fashion remains, and the girl who once spent all her time in jeans, sweaters and boots has become accustomed to dressing in the finest designer wear. In the process, she's become a fashion icon and is now a regular on "best-dressed" lists, including high profile plaudits from People and Vanity Fair.

Rumours of an imminent engagement reached their apex in late 2006, when Kate attended William's graduation from the elite Sandhurst military academy -- the first time she had been at a high-profile public event attended by the monarch and senior royals.

One tabloid even hired a lip reading expert, who revealed that Kate had declared as she spotted William in military dress: ''I love the uniform. It's so, so sexy.''

Yet, within months, the Prince was drawn away to his life in the Army and the pair decided to split up. But by July, 2007, the romance was back on, with new commitment.

Katie Nicholl, author of the book "William and Harry," says the couple made a secret pact when they reconciled in 2007 to eventually get married, after Middleton let it be known that she needed some assurance they had a future together.

"He promised her it would end in marriage, they would be together and that he loved her," Nicholl told CTV's Canada AM.

"Even though we've laughed and called her ‘Waity Katie', actually she will have the last laugh because she's going to get her prince."

William proposed while the couple was on vacation in Kenya in Oct. 2010, and he gave his bride-to-be the same ring his mother Diana had worn: an oval sapphire that is surrounded by diamonds.