Jazz dancers jam Latin style.

BUTTERFLIES AND carnaval puppets lent a Latin flair to Jazz Dance World Congress 2004, held in San Jose, Costa Rica, in late July. The congress, founded by Gus Giordano in 1990, attracted 250 adult dancers, 85 kids, and five companies, according to Ben Hodge, JDWC's executive director. Alejandra Gonzalez, who is proprietor of the dance studio Jazzgoba and this year's host, welcomed participants in the Herradura Hotel's La Paz Ballroom, followed by artistic director Nan Giordano's warning not to dash across the pista, a traffic-choked highway separating the hotel from a mall on the other side.

And then they were off, in a four-day blur of movement: Giordano company associate director Jon Lehr stood midfield in La Paz hollering, "Travel!" as rows of dancers, torsos contracted, and elbows hooked, sailed past him like a flock of birds. A sea of faces turned skyward and arms unfolded from high-fifth to second when Alberto Arias taught Zumba, an endurance class set to Latin rhythms. Trios of dancers learning Gus Giordano's Sing Sing Sing revolved like a Busby Berkeley kaleidoscope. For the first time this year, the congress included classes for 8-9 year olds.

Because participating companies were fewer than in previous editions, all of them were able to perform on every program. Many expanded the jazz idiom: Los Angeles' Instincts Live Media Dance Company danced a sleek Hollywood hipster tango; Japan's Masashi Action Machine tumbled and sparred in Black Belt; Giordano Jazz Dance Chicago orbited through a comic modern cosmos in Le Grand Futur is Here!; and Club Calloway, Utah's Odyssey Dance Theater toyed with hip hop and the Hustle (and elicited shrieks of terror from young viewers during a bloody excerpt from their vampire piece, Lost Boys). Gonzalez, meanwhile, drew gasps with her children's presentation, Our Rain Forest, which culminated in the release of 200 live butterflies onto the stage and into the audience. According to Nan Giordano, the tech crew, which had not been apprised of the plan, was taken aback, as were dancers, who found themselves sidestepping dying butterflies later that evening.

Still, a good time was had by all. Dave Massey's orgiastic Feeding took the gold in the Leo's Jazz Dance Choreography Competitive event; Tessandra Chavez won the silver, and Jen Hechtle-Bradford the bronze. Classes closed with the Jazz Jamm, during which participants learned a rapid succession of combinations from each teacher. At the outset of the event, Gonzalez and Gus Giordano drove into the ball-room in a convertible, accompanied by a folksy cimmarona band and dancing mascarada puppets. When the band stopped, a hush fell over the room as Giordano rose to speak. "How did I get into this?" he asked wryly as he surveyed the scene. "Look! When you're 80, this could happen to you."