Wyc and Corinne Grousbeck are having a few friends to their Edgartown Great Pond home this month to talk shop.

Boston Celtics coaching legend Arnold (Red) Auerbach and his former offensive star K.C. Jones will be spinning tales about the Celtics eight-straight National Basketball Association (NBA) championship streak back in the 1950s and 1960s - educating and entertaining the Celtics' newest majority owners.

The Grousbecks are also setting places for nearly two dozen paying strangers. A seat at this table costs $500 - a small price for those anxious to rub shoulders with basketball legends, eat a four-course meal prepared by the culinary team of Alchemy restaurant and kick back in the Grousbecks' second floor tower overlooking a pond cove.

"We're used to entertaining 19,000. This is not a problem," Wyc says with a wink Wednesday afternoon as he leans into a couch on the sun porch of their Machacket Neck retreat.

This crowd, Corinne suspects, could rival the enthusiasm of a full house at the Fleet Center during a Celtics game - especially when Red hands the guests a cigar and invites them to the porch for a smoke and a story. Corinne will whip up a batch of Celtic-green martinis. Wyc promises to ice down plenty of Budweisers - a nod to Anheuser Busch, official sponsors of the Celtics. The team's other part-owners, Glenn Hutchins and Bob Epstein, also seasonal residents of the Vineyard, will be be on hand to ham it up with Auerbach and Jones.

The whole affair is in the name of Island folks caught in the affordable housing crisis. The Grousbecks are but one of 12 seasonal households opening their Vineyard properties later this month and offering a bit of star power and fine cuisine to benefit the Island Affordable Housing Fund (IAHF).

Over the past four years, this nonprofit group has been bankrolling affordable housing efforts undertaken by housing agencies, towns and other nonprofits across the Island. They're hoping to pull in $250,000 this year. Each of the hosts is picking up the tab on food and drinks, so every dollar raised from ticket sales directly funds IAHF programs.

"We needed a vehicle to allow those more capable of stepping up to get involved," said Kenn Karakul, a member of the IAHF board who is heading up this "Guess Who's Coming to Dinner?" event.

This year's IAHF fundraiser detours greatly from the last three years of mid-summer auctions and dinners. In prior years, through Houses on the Move, the fund solicited Vineyard artists and craftsmen to create house-themed structures for a July auction and dinner at the Martha's Vineyard Agricultural Hall. "Guess Who's Coming" aims to grab the Island's high rolling crowd looking for an evening tailored to their interests to benefit a good cause.

"When planning this year's event, we started with the basic question: what's your favorite Vineyard evening? The answer was simple: being at a great house with interesting people," says Kenn.

Organizers also wanted to give their artists and designers a break and take a rest from the often-used auction fund raising tactic.

Word of the affordable housing problem has been rapidly spreading through the Vineyard's more affluent circles over the last few years. It's a door to door, person to person witnessing taking place. The Grousbecks got the affordable housing religion last year.

Kenn and his partner, Jim Heald, seasonal residents of Edgartown, philanthropists and former owners of the Home Shopping Network, asked the Grousbecks to host one of the dinner parties during a visit this spring.

"The minute Kenn and Jim walked in the door, they started talking about affordable housing," Wyc says.

The Grousbecks had already started to understand the problem through stories shared by their contractors, electricians and the staff at their favorite restaurants.

"We'd gotten to know a number of year-round families. I wondered how they made it through the winter," Corinne says. "Having money shouldn't entitle you to be here. These people are committed to being here 12 months of the year. Everybody sort of belongs here. It's an alchemy of people who all fit."

The lineup for this July 24 affair, in addition to sports, features culinary and literary luminaries and settings ranging from Chilmark oceanfront to a 90-foot yacht on Edgartown Harbor. Entertainment ranges from magic shows to stand-up comedy routines to political debates. Celebrities, of both national repute and Vineyard fame, are expected to make appearances at many of these dinner parties. The evening begins with a cocktail party at Nina and David Failkow's house in West Tisbury, where participants will receive maps to their dinner destinations.

Their party assignments will remain a mystery until the night of the event. Guests pick their top three choices when they register, and organizers plug them in to those with available seats. Ticket sales are very strong, Kenn says, but there is still room at some of these tables.

Corinne is convinced their gathering will appeal to the couple who might be on the fence about joining another fundraiser.

"The basketball angle is a big selling point. Talking sports is enough to get the men dressed up and out of the house for the evening," Corinne says with a laugh.

Their great pond retreat is surprisingly devoid of any hints of their profession - an intentional decorating choice. The only green and white is on Corinne, who admits that the color combination is popular this season and she's taking advantage of it. Tonal hues - matching those of the sandplain grasslands outside - cover everything from the kitchen counter to the formerly red circular couch they bought from the Fairmont Hotel in San Francisco.

For those Islanders unable to swing a $500 ticket for Saturday night's affair, they can join the cause Sunday evening for a night of music at the Hot Tin Roof. Johnny Hoy and the Bluefish, the Mike Benjamin Band and Boston band Suspect will be performing that night. IAHF officials will enlist manpower that night to build two houses this fall in a project sponsored by the local Habitat for Humanity and IAHF.

Tickets are $35 apiece and can be purchased at venues across the Island.