As the Impressionist and Modern sales last week demonstrated, there’s plenty of money available, especially from abroad, for the best works of art that come up for sale — regardless of the state of the economy. The auction houses have trimmed their sails but, even so, the Contemporary auctions — which start today at Christie’s and continue at Sotheby’s and Phillips de Pury this week — are overstuffed with product.

Sotheby’s evening sale of Contemporary art has 84 lots, which the house hopes will realize between $291 million and $360 million. That would be a big jump from last year’s $254 million total. Phillips de Pury’s evening sale is estimated at between $50 million and $72 million, even though its cutting-edge auctioneer did $33 million at the same sale a year before. The presale estimate at Christie’s is between $282 million and $399 million, well above the $225 million to $305 million presale estimate at this time last year — but not significantly above the $384 million total (including premium) from that landmark sale. The combined low estimate of the three evening sales is $623 million.

How to explain this heedlessly aggressive season? Are the auction houses being compelled by profit-seeking to drive themselves over a cliff of outlandish expectations? Or do they — with their constant encounters among both buyers and sellers — know something about the demand for contemporary art around the globe? The answer will make for a riveting spectator sport.

This auction season opens just as new reports have disclosed the buyers of four of last year’s biggest purchases. The Al-Thani family of Qatar bought the Rockefeller Rothko that went for more than $70 million, the Francis Bacon pope painting that went for more than $50 million, and Damien Hirst’s “Lullaby Spring” for nearly $20 million. The last purchase came six weeks after a similar work sold for a fraction of that price. Each of these sales has driven the Contemporary art market forward. The Art Newspaper, which reported the Al-Thani purchases, has also identified Ukrainian Victor Pinchuk as the buyer of Jeff Koons’s “Hanging Heart” for more than $23 million.

This news revives questions about whether the art market at its highest reaches rests on too few buyers. By the end of next week, we’ll know whether there are more Russian and Gulf States collectors lined up behind Pinchuk and the Al-Thanis. Or perhaps these important collectors have yet to slake their thirst for art.

Naturally, the sales are filled with works by Mr. Koons, Mr. Hirst, Rothko, and Bacon to test the waters. There are also plenty of Basquiats, Warhols, and Richters. For the spreading European taste in Yves Klein and Piero Manzoni, there are a number of well-priced lots available at Sotheby’s. Christie’s is heavy on Richard Prince, Willem de Kooning, and Roy Lichtenstein. Phillips de Pury has its usual array of such younger artists as Mark Grotjahn and Steve Parrino, but also significant works by Mr. Hirst, Mr. Prince, Basquiat, Richter, and Mr. Koons, too. That’s where the big presale estimate is coming from.

Setting aside the numbers for a moment, it is worth recognizing that the art market’s peak is bringing the highest quality works out into public view. Here is a tremendous opportunity for the enthusiast to see some extraordinary paintings. Take Christie’s “Double Marlon,” which has two stills from “The Wild Ones” printed one on top of the other on the right hand side of a large, unprimed canvas. The raw fabric soaked up the ink, creating a crisp registration, which is a prized quality in Warhol silk screens. In the same sale is a powerful Adolph Gottlieb, estimated at between $2 million and $3 million, whose work has been hotly traded on the private market. There is a Clyfford Still painting, estimated at between $8 million and $12 million, worth seeing for itself and for its kinship with Indian paintings of the same period.

Don’t miss Robert Rauschenberg’s “Overdrive” (1963), estimated at between $10 million and $15 million at Sotheby’s, or Tom Wesselmann’s “Great American Nude No. 48” (1963), estimated at between $6 million and $8 million. This Wesselmann installation ties together Rauschenberg, Pop art, and Matisse in unexpected and yet wholly intuitive ways.

Basquiat’s “Untitled (Prophet I)” (1981-82), estimated at $9 million to $12 million at Sotheby’s, and “Untitled (Fallen Angel)” (1981), estimated at between $8 million and $12 million at Phillips, show the 21-year-old painter doing some of his most compelling work.

One sign that these sales represent the peak of a market cycle is the feeling that the lots here are some of the best of a new canon. These sales lack the market-probing works of an early boom cycle. But like the Impressionist and Modern sales, they concentrate on the best works from the most esteemed artists. With Contemporary art these days, there are just more of them.