IN THIS ISSUE: Kate Middleton — Here Comes the Gown!

OK! IN THIS ISSUE: HOW KATE GOT WILLIAM TO PROPOSE!

"This dress has to be perfect," renowned British designer Bruce Oldfield tells OK!. "A hand-crafted piece of couture, using only the best materials; nothing about the fit or finish can be left to chance. It will be part of history."

Talk about a lot of pressure! The seriousness of the issue is why Kate is taking her time choosing a designer, but the announcement should be made fairly soon. British designers Phillipa Lepley and Bruce (a Diana favorite) are reportedly in the running, along with Daniella Issa Helayel, who created Kate's blue engagement dress, and Elizabeth Emanuel, who with her ex-husband, David, designed Princess Diana's wedding gown.

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And while Kate will be advised by Palace aides on protocol (no bare shoulders or anything too slinky), the final say on the dress will be left to the bride.

"Kate decides — with help from her mother," a royal insider tells OK!.

And once the princess-to-be has reached her decision on designer, the work has only just begun. The chosen designer will work with a small, trusted staff under high security which will include private garbage collection (to keep the curious from scrounging for fabric scraps) and guards, explains Camilla Tominey, royal editor of British newspaper the Sunday Express, and OK!'s royal expert in London.

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So while the world waits for Kate to announce the designer, the wait to see the style of the gown is just getting started. Kate will keep the design of the dress a secret until her April 29 wedding, but that doesn't mean one can't speculate as to the type of couture we'll see walk down the aisle this spring.

Stylist Anya Sarre has studied Kate's everyday style, which is a mix of trendy and traditional, and says to expect her gown to have that "something old, something new" mix.

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OK! also asked an esteemed panel of designers — including two in the running to design Kate's dress, Elizabeth and Bruce — to give us the inside scoop on the whole process.

When asked what they were designed if honored with the opportunity, Bruce replied: "A simple silhouette with sufficient detailing to give it a sense of occasion, but not so much as to drown her slight frame. Her dress might be traditional and elegant, possibly even demure, but I'm sure she would want a modern twist — a nod to fashion."

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Princess Di designer Elizabeth explains how "Kate has developed her own sense of style. She very much knows what suits her. I would imagine she would go for something quite simple. I'm pretty certain it's not going to look like Diana's dress."

"The most important thing is to do an absolutely amazing dress for the bride," Elizabeth continues. "The bride is the most important part of this at the end of the day. And...billions of people are watching, as well."