Prada's fall/winter 2010 men's runway show in Milan included a model in a navy blue blazer and khaki-colored trousers, an unmistakable signal that the preppy aesthetic was surging back into fashion.

So no real surprise, then, when spring brought word that Lisa Birnbach, co-author and editor of "The Official Preppy Handbook," is working on a follow-up to her Madras-print-covered bible for the boarding school set with "True Prep," due to hit shelves a month short of the original's 30th anniversary.

The new book is set for release Sept. 7, and in a recent interview, Birnbach said she's working with writer and graphic designer Chip Kidd, whom she credits with persuading her -- after they connected over Facebook -- to revisit the topic.

"Chip showed me what a huge afterlife the 'Preppy Handbook' had online. People were writing about the book and they sounded like they were in a desert dying for a drink of water. It was like: 'Lisa, please!' "

The book was still a work in progress, she said. "But the chapter on clothes is finished -- and I can tell you the title is going to be 'I Just Found It in My Closet.' "

And how might the contents of that closet have changed, exactly? "It's funny," she said. "In some ways, 30 years is a long time, and in some ways it's no time at all. We've got brands that didn't even exist then as well as some brands that were around but that we just hadn't included."

Birnbach reassures readers that many of the familiar favorites are revisited. Among them are Lacoste, Sperry Top-Sider, Brooks Brothers and Ralph Lauren. "I was very, very stingy with (Ralph Lauren) in 1980. I think he's referred to maybe once," she said. "But this time he gets a lot of play."

She said that some additions are labels that actually predate the first book, including Burberry, Barbour, Hermes, Verdura, Kenneth Jay Lane, Hunter Wellies and J.M. Weston.

But the most interesting ones are the brands that weren't even born yet. "We've got Vineyard Vines -- they started in 1998 -- and of course J. Crew -- which wasn't around then either (it launched in 1983 as a mail-order company). And we've got some Kenneth Cole (1982) and a little bit of Robert Graham (2001)."

Birnbach said a good example of a modern women's label that "touches just the right nerve" is Tory Burch, who didn't open her doors until 2004.

"She has comfortably priced, sporty clothes. She has her finger in a lot of different pots now, but when she started out it was exactly the kind of thing we could wear to work, to the book club and to the country club -- those sort of David Hicks-inspired printed shirts," Birnbach explained. "And she makes this big beach towel that's sort of like an Hermes towel."

Expect "True Prep" to reflect current reality beyond name-checking the nouveau-prep brands. "There's a lot more upmarket stuff, but there's also a lot of down-market stuff" in the book, Birnbach said, "because fashion in this decade is a lot more about the high and the low."

Another difference? "I don't want to give too much away, but I will tell you that the body is shown much more vividly (in this book)," she said. "There's a piece about how stretch (fabric) has arrived in our midst and how that allows clothes to actually fit. Thirty years ago, we were trying to hide our bodies; now we're not hiding them. Things like khakis look and fit better."

The follow-up book has 12 chapters (five more than the first), presumably swelling in part to accommodate the tackling of new preppy-vexing topics like technology (no texting at the table!), rehab and reality television.

Birnbach noted that there are a lot more specific brands included, clothing and otherwise, because many of the hand-drawn illustrations of people and places have been replaced by photos.

"So we have some Jonathan Adler interiors, for example, and I don't know if we even included Belgian Shoes in the first book, but they end up having a real place of honor in this one," she said.

Despite sounding like a paean to conspicuous consumption, Birnbach said that instead of reflexively trying to max Mummy and Daddy's Amex Black at L.L. Bean or Lilly Pulitzer, the true spirit of prep demands that prep-pies dig through their closets.

"The point I'm trying to make in this book is that yes, you can buy new clothes, but you can also rely on the things you have in your closet."

"Anything old is preppier than anything new -- that's just a rule."

The '80s live on

Some key dates in the preppy movement occurred well into the decade. And after.

As Birnbach notes, in some ways the 30 years between the publication of "The Official Preppy Handbook" in 1980 and "True Prep" in 2010 feels like a very long time, and in some ways like no time at all.

--1983: Arthur Cinader and his daughter Emily launch a mail-order catalog called J. Crew, which, in 1989, will become a bricks-and-mortar retailer and establish itself as a crucial curator, and supplier, of the preppy aesthetic.

--1984: The movie "Preppies" tries to capitalize on the craze with a big-screen comedy. The movie poster features a fellow in khaki shorts and polo shirt gripping a gun, along with the tag line: "Robert 'Chip' Thurston III will inherit $50,000,000 ... If he survives the weekend."

--1989: George Herbert Walker Bush takes office, becoming the preppiest occupant of the Oval Office since JFK, although, by failing to make the gin and tonic the national libation, he stops short of completely pandering to the preppy constituency.

--1998: Brothers Shep and Ian Murray launch a line of all-over nautical and animal print neckties inspired by Martha's Vineyard, and Vineyard Vines is born.

--2000: Official outdoor outfitter of prepdom and fixture of Freeport, Maine, since 1912, L.L. Bean opens its first retail doors outside of Maine.

--2004: The eventual proprietress of an entire preppy-bohemian luxury empire, fashion designer Tory Burch launches her label from an Manhattan apartment.

--2006: Brooks Brothers announces a collaboration with designer Thom Browne -- the official tortured soul of the neo-preppy brat pack. Dubbed "Black Fleece," it will debut in fall 2008 and be the perfectly balanced marriage of the former's rich preppy heritage and the latter's updated approach to tailoring and details.

--2007: "Gossip Girl," a TV show that follows the lives of a pack of Manhattan private school nouveau-prep teens, debuts on the CW.

--2008: Designer Scott Sternberg's Band of Outsiders label turns the Sperry Top-Sider inside out. The collaboration, and the deconstructed kicks, help give the humble boat shoe an updated cachet of cool.

--2009: Harvard University inks a 10-year licensing deal for a line of preppy menswear, inspired by vintage photos of students on the campus, and called Harvard Yard.

--