TRUE PREP: It’s a Whole New Old World. By Lisa Birnbach with Chip Kidd. Alfred A. Knopf. September 2010. 256 pages. $19.95, hardcover.

There is no more singular or peculiar strain of American than the White Anglo-Saxon Person known as “the Preppy.” It’s not just the technicolor dress code, the proper secondary school and appropriate (Ivy League) college. It’s beyond the almost vertical family tree, the return address to a handful of cities and appropriate family crest of the pinkie ring. The Preppius Maximus is a species of such unique habits and forms, it warranted a true sociological breakdown.

In 1980, writer Lisa Birnbach recognized the nuances of the culture and created the original field guide to the clench-jawed and hair-banded: the plaid bound paperback Preppy Handbook, which swiftly became the field guide to the old money, very privileged and not particularly interested in the lower echelons (beyond the help, of course!)

The book became an instant bestseller, copies being snapped up, celebrated, talked about and given as (gag) gifts in places like Newport, Palm Beach, Grosse Pointe, Shaker Heights, Princeton, the upper East Side, Nantucket, Hyannis and yes, even Edgartown. Given that prep culture had long been the world that time forgot, no need for an update seemed to be necessary.

Until now.

Two decades — and such extreme social, technological and even economic shifts later — Birnbach has teamed with Knopf designer and writer Chip Kidd to chronicle the evolution of those who would deem NOKD (“Not Our Kind, Dear”) anyone who couldn’t tell their Vineyard Vines from their Ralph Lauren or who would shrink from the thought of sporting Lilly Pulitzer Capri pants.

The Prep Pantheon identifies the key prep icons (Kennedy, the Obamas, Ben Bradlee, Al Franken), but True Prep also includes the Prep perps — brought down for forgery, prostitution, embezzlement, murder (Jean Harris, Sydney Biddle Barrows). Because even felonious folks of certain pedigrees know how to fall from grace with a modicum of taste.

True Prep — appropriately subtitled It’s A Whole New Old World — is the new field guide to the ways of the blue blood, Blue Booked and quite possibly blue ticked. Recognizing that many social structures have evolved profoundly, there are now chapters for dealing with stepchildren, new spouses, gay couples, the eradication of many opportunities for prep employment and the 21st century of means for Mummy’s need to define herself (repeat: decorator, docent, real estate, yogini/shaman/healer).

For those looking to ascend to true prepdom, fear not. All the key brands of clothes, luggage, loafers are included — as is a reading list of the kind of books the elite and unaware have enjoyed for years. There is a diagram for dancing, a four step rites of lunging at a member of the opposite sex and a map of the brain/thought of one’s black Lab. Just as importantly, recipes for bland WASP food and — more importantly — cocktails are included, as is a section on the new economy (what to do with a store credit?) and the proper way to weekend (hint: it’s a verb, not a noun).

With tongue firmly in cheek and fingers always on the pulse, the greatest truth of True Prep is the gift of laughing at oneself. Effervescently capturing the strange realities of prep life, it is funny — even to the ones living it — with its silliness, charming in its will to be so utterly unto itself.

If you or someone you know fits the bill, this is the way to remove the sting. Even better given with a pitcher of stingers and a long afternoon to laugh at page after page of field reporting from the right stores, clubs, towns and colleges, True Prep is cheap admission to somewhere jubilant you may already be residing.