Leading museum directors and archaeologists from around the country will gather at the New York Public Library today for a major symposium on the collecting of antiquities.

The trade in ancient art has been scrutinized in recent months amid investigations into looting and demands by several countries that disputed pieces in American museums be returned. While the controversy has sparked a feud among many archaeologists and museums over the ethics of antiquities collecting, the debate has largely played out in the press. Today’s day-long forum, organized by the Association of Art Museum Directors, will bring more than a dozen prominent scholars to the same stage.

Led by the Archaeological Institute of America, some archaeologists have long argued that the collecting of antiquities by museums encourages the looting of ancient sites. Museum directors had remained quiet on the issue, but several have spoken out in the months following a landmark accord in which the Metropolitan Museum of Art agreed to return 20 disputed objects to Italy.

“Museums have in the past allowed themselves to be put on the defensive,” the director of the Art Institute of Chicago and an organizer of the forum, James Cuno, said. Mr. Cuno, who is moderating two morning panels and is sitting on one in the afternoon, said museum officials would likely make the case for “encyclopedic” museums that present artifacts from a wide range of cultures and historic periods. They say such museums would be threatened by policies that limit collecting to antiquities with a complete provenance, which they argue are exceedingly rare.

To many archaeologists, objects have little value if it isn’t known where they were found, and what other artifacts they were discovered with; museums contend that this lack of context does not diminish the artistic beauty of a piece.

In a move that has irked some archaeologists, organizers have set up the symposium so that museum officials can present their case in the morning before leading archaeologists “respond” in the afternoon. Still, the president of the AIA, Jane Waldbaum, has agreed to participate, as has Malcolm Bell, an art history scholar at the University of Virginia who led the push for the Met to return a set of Hellenistic silver that Mr. Bell claimed had been looted from Morgantina, in Sicily. The museum is returning the silver as part of its February agreement with Italy.

Among the other scheduled participants in the symposium are the director of the Met, Philippe de Montebello, and the head of the British Museum, Neil MacGregor.