Basel, Switzerland — After 39 years in the business, Art Basel is the queen of Modern and Contemporary art fairs. Gallery owners, critics, art dealers, and artists — as well as the sales — confirm the title.

This great bazaar opened yesterday, just as it has every spring since 1970 in the quaint but industrial city of Basel, Switzerland. More than 2,000 artists from 30 different countries are represented.

The director of Barcelona’s Galería Joan Prats, Gloria Pérez, is participating in the commercial exhibition for the 42nd year in a row. “Everybody wants to be in Art Basel,” she said. And it’s the “outstanding quality” of the work shown, she says, that makes the fair so attractive.

About 99% of the galleries reapply every year, and only those that ran out of business don’t consider coming back. But making it into the fair is not easy — and having been accepted once is not a free ticket for future years. A record 1,100 applicants tried to get a booth for the 2008 fair, but only one-third managed to be approved by the highly demanding selection committee. Being admitted to Art Basel is a safe bet on good revenue: Ms. Pérez is expecting to sell 70% of her contemporary paintings.

“The turnout is very good,” the owner of the Manhattan gallery Alexander and Bonin, Carolyn Alexander, said. “I was insanely busy on the opening day.” During her first 24 hours in Basel, she got two good holds on her most expensive piece, a $1.1 million sculpture by Colombian Doris Salcedo.

Sales, of course, are the reason for the fair, and questions of global economic stability could hold some buyers back. Still, the number of record sales reached in the last round of art auctions suggests that the art market is at least somewhat immune to the consequences of larger economic crisis. Art Basel would be a good indicator of how things are progressing, except that the Swiss executives who operate it claim not to have the total revenues of the fair: What counts to them is that people keep coming back. And they definitely do.

One issue that does pop up is sponsorship. Art Basel’s director of operations and finance, Marc Spiegler, said that his “major concern” was focused on how the crisis was going to affect the corporate partnerships of the fair. But even that turns out to be on solid ground: A three-year contract with its major sponsor, UBS, has just been signed.

In 2007, attendance exceeded 60,000 people. Among these are art professionals, but there are also many art lovers who could never even afford the frames that hold the paintings. The museum-style design of the exhibition reduces the commercial feel, and makes it accessible for those who aren’t in the market for million-dollar works of art.

“A selection committee inspects the booths at least twice during the fair in an attempt to judge the stands that are too commercially installed,” Mr. Spiegler, one of the three directors of Art Basel, said.

One of the main reasons for the success of the world’s biggest contemporary art fair is the mix of works; while some date back to the early 20th century, others were finished last week.

“The most recent work gains a certain kind of serious and historical grounding because of the presence of the more historical work; and historical work is often animated or made more vivacious [because of the new],” Mr. Spiegler said.

Another key factor for the show’s success is the audacity it has shown ever since the first year. Its organizers have been relentlessly innovative, and never hesitate to include new artistic developments, such as photography or video. Art Unlimited is one of the latest additions to the show. This section, created in 2000, is devoted to those artists deemed “too ambitious” to have their works placed within a traditional booth. Those monumental-scale pieces are among the gems of Art Basel 2008, and not because of their size, but because of their originality. They will be hard to miss.