LONDON >> Goodbye Waity Katie. Hello Princess Catherine.

The transformation of Kate Middleton, which began in earnest with the announcement of her engagement to Prince William last fall, is nearly complete now that she and her prince have toured the country ahead of their April 29 wedding at Westminster Abbey.

The young woman whose natural ways and wholesome good looks charmed the nation when she hit the scene eight years ago as William’s girlfriend is soon to be replaced by a new, glossier version, more chic and trained in royal ways.

In movie terms, Middleton, 29, is ready for her close-up, having endured a lengthy courtship with several breakups along the way. Through it all, she’s shown herself to be a formidable woman who knows exactly what she’s getting into, harboring respect but not awe for the royal family she will soon be joining — and perhaps revitalizing.

The former college girl is a future queen, unless death, divorce or revolution intervene. That gives her words, deeds — and even her fashion choices — a gravity they did not carry before. But she must continue to demonstrate patience and staying power, since it may well be several decades before William becomes king.

Much has been made of Middleton’s "commoner" background. While it’s true she does not come from an aristocratic family, she has been raised in affluence, with her successful parents able to send her to an exclusive boarding school and to the University of St. Andrews in Scotland, where she met William when they were first year students studying art history.

They were friends at first, part of a small group of upper crust chums, but became romantically involved soon afterward, spurred reportedly in part by William’s presence in a front row seat for a charity fashion show at which Middleton wore an eye-catching see-through dress over matching black underwear.

They kept their romance largely under wraps until William let down his guard a bit during a 2004 ski vacation and was seen with his arm around Middleton as they waited to board a lift. They looked very comfortable together — and seemed to be in love.

One of the knocks against Middleton has been a whispering campaign that she set out intentionally to catch a prince, perhaps even choosing St. Andrews because she knew William would be there. Whether rooted in fact or just envy, those rumors have never been completely dispelled.

During the long years of courtship, Middleton shunned the press, never granting an interview in which she discussed her feelings for William or the royals. People may think they know her personality but for the most part they are basing their judgments on appearances and expectations, not on anything Middleton has shared with the public.

"She understands the importance of mystique," said British historian Andrew Roberts, who predicted that Middleton — like Queen Elizabeth II, will never give an extended, tell-all interview like the ones Princess Diana gave when her marriage was collapsing.

The only public hint of Middleton’s feelings came the day last November when the engagement was announced. She and William met briefly with the press and she told reporters she was somewhat intimidated about joining the royal family in such a prominent role.

"It’s quite a daunting prospect but hopefully I’ll take it in my stride," she said as television cameras whirred. "But William’s a great teacher so hopefully he’ll be able to help me along the way."

In the short appearance, Middleton also denied persistent reports that she had kept a poster of Prince William on her wall when she was growing up and spoke about the late Princess Diana in glowing terms.

Since then, she has made a series of appearances with William and has seemed to thrive on having contact with the British public, even as she does seemingly mundane tasks like lowering a flag to start a foot race.

In the years before the engagement, Middleton adroitly avoided being photographed in any way the could detract from her dignity. When her colleagues on a rowing team posed topless covered in body paint for a charity calendar, Middleton refused her friends’ pleas and stayed away.

While others in her crowd, including William and Prince Harry, were occasionally snapped leaving nightclubs looking somewhat inebriated, Middleton made sure she looked composed before walking out the door, figuring — usually correctly — that the paparazzi would be waiting.

"She has done this superbly, which shows she has her head screwed on right," said Roberts.

The only pratfall came at another charity event when Middleton took a tumble on inline skates while wearing bright yellow hotpants with a sparkly green top and pink leg warmers. She landed in an undignified position as the paparazzi snapped away, but she was able to laugh the whole thing off.

Indeed, it is her good humor that seems to win people over. She is not typically glum, and her zest seems to rub off on William.

Since graduating in 2005, Middleton has worked part-time for clothing company Jigsaw and has devoted much of her time to helping her parents and her brother and sister run the lucrative family business, a party supply company called Party Pieces.

She has shied away from pursuing an independent career, and has not stated publicly how she views her future role in the royal family once she becomes a princess.

There are indications she plans to be involved in charity work, although her specific interests are not yet known, and it is also possible she and William will try to start a family fairly soon.

To say there would be high national interest in her producing an heir is probably an understatement.

Some people hope that she can break the royal mold completely.

"I want to see something interesting from her," said student Ursula Sam, 22. "Diana was the best for charity work, so Kate shouldn’t copy her. Do something different. Be a cupcake maker or something."