Hadid in America: a lightness of being: with the completion of her Contemporary Arts Center building in Cincinnati and the unveiling of her plans for the Price Tower Arts Center in Bartlesville, Okla., Zaha Hadid adds two strong designs to her growing oeuvre - Architecture

The white cube, virtually unchallenged as the reigning' museum and gallery paradigm, is a relatively recent, largely postwar phenomenon, perpetuated by the argument that it provides the ideal neutral background for viewing art. No environment, however, is really neutral, not even the white box, which originates in clinical attitudes that infiltrated modernist design many decades ago via the laboratory and the scientific notion that close study under ideal conditions reveals the "objective" truth about an object. Museum labels themselves are usually clinical--name of artist, title and date of work, materials, dimensions--as though data were content. The white box is, in fact, philosophically and optically freighted. As in a surgical theater, art is observed under bright, even, shadowless light. Each work is isolated in a space of its own distinct from others and distinct from the space of the "objective" observer. Like riders in an elevator never making eye contact, museum visitors are themselves detached even from each other. The white box is a constellation of objects and viewers cast in separate, nonintersecting orbits.

New York's Museum of Modern Art is the most famous adherent and vigorous advocate of the white cube, but even Frank Gehry's Guggenheim Bilbao, so turbulent on the outside, respects the concept and convention inside. Its ceilings--with chimneys that funnel light one or two stories down--may be complex, but the light finally arrives in galleries that are basically white boxes.

In May, the Contemporary Arts Center (CAC) inaugurated its new structure, called the Lois & Richard Rosenthal Center for Contemporary Art, located on a tight corner site in downtown Cincinnati. The institution that went to court over its right to show Robert Mapplethorpe's photographs proved its independence and character again by supporting another way of seeing art. Zaha Hadid has built a museum that is immersive. The space of the viewer mixes with the space of the art in a simultaneously interactive and intersubjective environment that is experiential rather than detached and clinical. Hadid injects subjectivity into the delicate equation of how a building sets up ways in which to sense and understand art.

The CAC structure is Hadid's first built work in the United States, and the first major museum in the country designed solely by a woman. Its completion coincided with the unveiling of plans for Hadid's second building in the U.S., the Price Tower Arts Center in Bartlesville, Okla., with an opening date planned for 2006. Specializing in design and architecture: with an outstanding collection of material from the eccentric Oklahoma architect Bruce Goff, the Arts Center will stand next to the Price Tower, a 1956 landmark designed by Frank Lloyd Wright.

Born in Baghdad in 1950 and based in London, Hadid is a master storyteller, only she spins her tales with space, over time, in an unfolding narrative graced by optical illusion. In Cincinnati, she captivates her audience with the structure's profile. Pedestrians blocks away are caught by the abstract form of the seven-story building, a bundle of long thrusting elements hovering above their own shadows. The corner site, as a parcel of real estate, implied a rectangular building, but the long concrete prisms originating at the far end of the site power their way through the boundaries of the opposite cur net, shattering the zoning envelope. The projections that break through the virtual walls of the site reach into the space of the viewer, like the Prouns of El Lissitzky, which transgress their frame to step into three dimensions. Perspective reverses direction, reaching forward rather than receding into depth.

Though this bundle of horizontal volumes claims its own space and takes urban center stage, the building diplomatically responds to its context by suturing the opposing sides of Sixth Street, on which it fronts. Modernist concrete behemoths on one side of the street face the inure fine grained texture of the 19th-century brick city on the other; Hadid negotiates a transition between the two with concrete prisms that abstract, and horizontalize, the nearby brick buildings.

Having set the scene, Hadid invites the visitor into her narrative. Floored in simple concrete, the lobby visually extends the sidewalk inside through its glass walls, as though blurring the boundary between interior and exterior. There is no exterior flight of steps, no plinth or pedestal, to imply notions of lofty edification; the building occupies the city's pedestrian space. The concrete paving crosses the ground floor to the rear wall, where it turns up in a gentle radius and rises six floors to the skylight: what Hadid calls the "urban carpet" turns the horizontal introduction to her story vertical, as it sweeps up to the irresistible "UnMuseum" for children on the top floor.

A composition of lights set into the lobby ceiling and flour in forced perspective leads the way from the entrance toward the long, black aluminum-encased stairs that scissor their way up the light well, close to the back wall. Visitors plunge into the story line, their curiosity piqued, heading up into unknown territory. Nothing about the exterior really explains in advance what the interior will hold and where the spatial narrative will lead.