Paintings in the show take expansion literally.

As contemporary art continually stretches and redefines itself, the concept of sculpture has broadened to include installation, photographs, environment and events. Similarly, painting has been challenged and redefined by photography, digital imagery and interactive, experiential art. And there is a slowly emerging sense that "painting" is an aesthetic attitude, not just the literal application of paint to a surface.

Prague Biennale 2, which displays works by more than 200 international artists in the spectacular postindustrial space of Karlín Hall, addresses this issue in "Expanded Painting," the largest and most significant of its individual sections. Curated by the directors of the biennale and editors of Flash Art magazine, Helena Kontová and Giancarlo Politi, "Expanded Painting" both acknowledges contemporary art's debt to early modernism and also traces the broadening of the concept of painting to incorporate video, installation and other media, as well as actual painted works.

The beautiful and haunting paintings of Michael Borremans from Belgium are relatively traditionalist in style - elegant portraits of women created with loose, sensual brushstrokes. Yet the subdued, nearly black-and-white palette and repeated views of women, often viewed from an unexpected angle, with bowed heads and strangely unengaged hands, held limply and close to the body, are resonant of film or dance.

Kirk van den Broerk's bleached-out images of pavement edges or expanses of ground create the sense of being made with a rushed, hand-held camera and manipulated exposure. Maurizio Cattelan's Zorro (with the famous ‘Z' cut into a purple square) from 1995 is a playful reference to the slashed canvases of revolutionary Italian modernist Lucio Fontana, while simultaneously referring to the swashbuckling elegance of the television hero.

German artist Anselm Reyle's two works are vibrant expressionist pieces drawing on formalist principles. In an untitled work from 2005, a sheet of shiny mauve cellophane is crinkled onto a flatly painted canvas of the same color. The work has stunning abstract qualities of drama, energy and dynamism.

Two framed video pieces by Luca Rento of Italy perhaps exemplify the concept of "Expanded Painting." Dream On and Breath present light, misty, romantic images of a beautiful, sleeping pink-cheeked boy and a woman seated beside a lake. They appear to be paintings, but the boy's chest gently rises and falls with his breath, and leaves on trees beside the lake occasionally tremble in the breeze.

Prague Biennale 2 Ends Sept. 15. Karlín Hall Thámova 14, Prague 8–Karlín. Open daily noon–7 p.m.

The second of the biennale's two major group exhibitions, "Acción Directa," presents politically activist art from South America. The works in this section are worthy, but are tucked into a dark corner of the exhibition hall, which accentuates their conceptual rather than visual aspects and frames them, perhaps unfortunately, as rough and homegrown. Most poignant are small makeshift shelters built from folding picnic tables and faded sleeping bags by Alexandre da Cunha of Brazil.
The other sections vary in their liveliness and accessibility. "New Perspectives in Chinese Painting" is a strong and vibrant series of images addressing issues of exoticism and commercialism. "Definition of Everyday," curated by a team of young Czech art intellectuals, is disappointingly dry and esoteric, yet challenging and visually distinctive in shades of black, white and gray.

Perhaps the most successful section, with effective installation of the works as well as strong local appeal, is "Czech and Slovak New Scene." This selection of works by established and emerging artists is irreverent, humorous, humanistic and intelligent.

Among the most thought-provoking pieces are Slovak artist Ilona Németh's Pax (2005), a subtle and darkly hilarious piece. At first look it is a walk-in wardrobe in the Ikea style - both the object itself, built from laminated wood, frosted Perspex and metal-effect handles, as well as the accompanying marketing brochure. On closer inspection, we see it is a ready-made confessional, with two side booths connected by a grille to a central section for the priest, with a purple velvet cushion and smart, ambient lighting. The piece deals with the notion of buy-in, do-it-yourself religion - mass-produced and with a false sense of comfort.

In the same section, Kryštof Kintera has several installations, adroitly placed against rough walls and tucked into corners so that they surprise and amuse. Revolution (2005) is a model of a toddler or diminutive man right next to a brick wall, against which it periodically bashes its head with a burst of rapid-fire sound.

David Černý's Shark (2005) is a typically heavy-handed prank by this Czech artist in which he has recreated the famous object by Damien Hirst of a shark in a tank of formaldehyde - only Černý's tank contains a model of Saddam Hussein in loose white underpants, with a noose around his neck.

Prague Biennale 2 is big and unruly, as one would expect from any biennale. But on a low budget and with imagination and energetic drive, the organizers have managed to bring together a lot of works that represent some significant strands of contemporary art.