Landscape's architect.

Winner of the Pritzker Architecture Prize in 1991, sixty-four-year-old Alvaro Siza, Portugal's most renowned contemporary architect, is known for his geometric deformations, his controlled composition of interiors, and his fascination with the everyday architectural forms of the modern urban landscape. If you add to these obsessions a "nostalgia" for the foundations of Modernity (Loos, Taut, Oud), a framework within which to read the work of this marvelously inventive architect begins to suggest itself.

His proposal for a new museum of contemporary art in his hometown of Porto evinces Siza's penchant for asymmetry, his skill in transforming a preexisting structure from the inside and in channeling light to construct a new space. In this unfinished project, to be built on the grounds of the manorial home that is now the Serralves Foundation, Siza will doubtless surprise us again with his ability to suggest permanence while linking disparate architectural periods through minimal, apparently simple means.

Siza's first work, Quatro Casas em Matosinhos (Four houses in Matosinhos, 1954-57), in the north of Portugal, already embodied the stripped-down structures that were to serve as the foundation of his oeuvre. The organicism of these houses echoes the architecture characteristic of the region, while his subtle torsions of the geometry of standard rooms give each interior space a particular definition. On the outside, tall, narrow slits cut into a wall beneath an exterior staircase reveal Siza's predilection for filtering local forms through the language of Modernism. Yet he does not specifically attempt to integrate the traditional and the Modern (these are small urban homes), but, rather, to break with the conformist '50s-style modernism of the buildings that line the street.

Similarly attuned to its environs, Casa Alves Costa (Alves Costa House, 1964-68), in Moledo do Minho, reflects Siza's sensitivity to landscape and the qualities of light in a given region. Featuring intersecting planes, an opening onto a small pine forest, and an almost naked street-side facade, this extremely delicate, albeit complex living space is marked by such carefully thought out, almost imperceptible details as wood-leaf wainscoting painted a very pale yellow, placed precisely at the point where the sun penetrates the interior.

The Pinto & Sotto Mayor Bank in Oliveira de Azemeis (1971-74) is a work whose geometries are even more "abstract" than those of Siza's earlier small-scale projects. Traversing various dimensions of the space, they construct a captivating box in which all the seemingly neutral shapes, painted white, gain expressive power, color, and drama. From the outside, the corner seems huge, despite the delicate scale of the building. The suave horizontality of the window frames, of the blinds, and the horizontal supports converge and summon light, while massive planes climb and delineate the interior space - details that recall early Modernist experiments. But here formal play is uncoupled from the naive utopianism of those times and becomes a knowing articulation of passages and themes that are then given to us in ruptured and discordant form.

In 1977, Siza was asked to leave the verdant hills and stone buildings of northern Portugal for the whitewashed, baked-red-clay landscapes of the south. There he began the construction of a vast neighborhood - at twenty-seven acres almost a new city - just outside the old town of Evora. This development, Quinta da Malagueira, is still under construction, constantly supervised by Siza. Here the architectural forms typical of the Alentejo, square houses painted a blinding white with broad chimneys and few windows, confront Modernist volumetric experiments, conferring on this part of the city a uniformity that is, however, subtly disrupted by a modern version of an aqueduct consisting of above-ground supply lines. Tempering what might otherwise be too "white and orthogonal" a site, this structure, arching over the neighborhood, seems to avenge the absence of history that any city built from the ground up necessarily represents. Here, Siza's apparently simple mixture of typologies results in an impressive urban complexity.

International recognition came to Siza in 1980 with his design of the Schlesisches Tor, a large public housing block in Berlin. Many have read this project, Siza's first to be built abroad, as the embodiment of the "contextual" qualities of his architecture, seeing proof of Siza's trademark sensitivity to his surroundings in the rhythms of the windows, in the apartment block's evocation of the street's curve, and in the slit between the new and old buildings. I prefer to see it as a mirror of the melancholia of urban life. Now known by the name Bonjour Tristesse scrawled clandestinely on its facade, the Schlesisches Tor - with its outer wall of identically sized windows - is animated only by the abstract evocation of a horizontal line, broken by a small dip as the building encounters the sky - ruefully reminds us that architecture is not, after all, always a joyful reflection of contemporary living.

Back home, Siza - much to the surprise of many critics accustomed to thinking of him as a modernist architect - agreed to rebuild the city's historic shopping district, the Chiado, which had been destroyed by a huge fire in the summer of 1988. His rigorous redesign project of the former buildings, which includes maintaining some of the old facades, entrusts time to return and breathe life into a neighborhood that dates from the time of the Marques de Pombal. In the Chiado, Siza, the great hero of Portuguese modernity, was humble enough to develop a schema that will slowly come not only to reflect but to form the history of the city to which it is integral.

Of Siza's most recent unrealized projects, his entry in the international competition for the design of the Helsinki Museum in 1993, is for me the most enchanting and moving. Not only the form but the site "capture" geometries that seem to traverse the city, but most impressive is the delicacy of the cuts through which light enters, the obsession with which they channel, divert, and celebrate that light in room after room. "A good museum should be, above all, a marvelous building," says Siza, and such was his design. Sadly, Helsinki missed its chance to house an exemplary work of a Portuguese master who has left traces throughout the world.

Manuel Graca Dias is an architect who has written numerous articles, as well as television and radio programs, on architecture.