Since its founding in 1987, Vilnius Jazz has earned a reputation of a radical avant-garde festival oriented towards originality and limit-stretching creativity.

This avant-garde festival had already raised a torrent of the mysterious vibrations that Mr. Shipp described.

Mr. Giffoni said he was inspired by a 2002 avant-garde festival in Minneapolis.

Jacob's Pillow, she was repeatedly told, had a conservative audience summering in the Berkshires and was not an avant-garde festival.

When the three-week avant-garde festival begins at Alice Tully Hall on July 11, it will be starting its fifth season.

If she has introduced avant-garde elements, she deliberately has avoided turning Jacob's Pillow into an avant-garde festival.

"It was never intended as a straight avant-garde festival," Mr. Rockwell said recently.

Many will be part of an avant-garde festival organized by the director Peter Sellars in November and December.

The three productions constitute an avant-garde festival.

Since 1948 Rossif actively collaborated with the Cinémathèque Française, organizing, among other things, an avant-garde festival at Antibes in 1949-50.