Ready with a full martini bar, an all-star auctioneer and over 75 artistic pieces up for bidding, Artspace is in the midst of final preparations for its annual Gala Benefit Auction this Saturday evening.

The program will feature both a silent auction of works culled from the gallery’s Flatfile collection and a live auction of more than a dozen marquee items, with proceeds to benefit Artspace. Guy Bennett, senior vice president at Christie’s auction house and a celebrity within the rarefied world of art auctioneering, will preside over the live auction in the nearby Wachovia Bank building on Church and Crown streets at 6 p.m., after guests have had a chance to bid on silent auction items at the gallery. Artspace Executive Director Helen Kauder said the live auction will be most dramatic portion of the evening.

“It’s real theater to watch, even if you’re not interested in buying the art,” Kauder said. “Guy Bennett will do a great job of getting the bidders excited and competitive.”

Live-auction pieces will include works by acclaimed artists both living and dead: Depression-era photographer Walker Evans, contemporary painter Christopher Mir and the late conceptual artist Sol LeWitt. The works of Sam Messer, associate dean at the Yale School of Art, and Robert Taplin, critic in sculpture at the Yale School of Art, will also be sold at live auction.

Many of the pieces were donated by the Yale University Art Gallery. Artspace volunteer Kjell Wangensteen SOM ’07 said the most anticipated live-auction items are a private tour and picnic at Philip Johnson’s Glass House in New Canaan, Conn. and a special surprise item to be presented by Bennett.

“I think Guy Bennett may be the biggest draw of all,” Wangensteen said. “He did a live auction at Artspace two years ago, and it was a big success.”

The majority of the works up for sale on Saturday are featured in the silent auction. Those pieces are currently on display at the gallery and are already open for bidding. Taken from the Flatfile, Artspace’s extensive permanent collection, the silent-auction works represent a generous survey of the many different worlds and visions offered by Artspace’s regular phalanx of area artists.

“We probably have about 120 different artists in the Flatfile,” Gallery Director Denise Markonish said. “I’d say about 90 percent of them are being featured in the silent auction.”

Kauder said that because the Gala Benefit Auction is an annual event, and because the Flatfile is constantly expanding, Saturday’s event will be a welcome opportunity for Artspace patrons to take stock of the gallery’s recent evolution.

“All the artists in the Flatfile update their portfolios, and then we pick one or two pieces out of there, so these pieces will represent what they’ve been doing over the past year,” Kauder said.

Advance tickets for Saturday’s event are available for $75 online, and tickets will be available at the door for $100. Wangensteen said he hoped to see a turnout of about 150 guests. All money raised at the event will go to Artspace, a nonprofit with an annual operating budget of less than $400,000.

“It should be a great event,” Wangensteen said. “And after all, it goes to a good cause.”