SANAA

For more than 15 years, architects Kazuyo Sejima and Ryue Nishizawa have worked together in their collaborative partnership, SANAA, where it is virtually impossible to disentangle which individual is responsible for which aspect of a particular project. Each building is ultimately a work that emerges from the union of his two minds. Together they have completed major commissions such as the Nagano O-Museum  and the Kanazawa 21st Century Museum of Contemporary Art (both in Japan), the Glass Pavilion of the Toledo Museum (Ohio), the De Kunstline Theatre and Cultural Centre (Almere, The Netherlands), the New Museum of Contemporary Art (New York, NY) and the recently opened Rolex Learning Centre (Lausanne, Switzerland).

Sejima and Nishizawa's buildings seem deceptively simple. Architects have a vision of a building as a continuous whole, where physical presence recedes and forms a sensual background for people, objects, activities and landscapes. They explore like few others the phenomenal properties of continuous space, lightness, transparency and materiality to create a subtle synthesis. Sejima and Nishizawa's architecture is in direct contrast to the pompous and rhetorical. Instead, they seek the essential qualities of architecture that translate into a simplicity, economy of means and moderation that are highly valued in their work.

This economy of means, however, does not become a simple operation of reducing the architects' workforce. Rather, it is intense and rigorous research anchored in hard work and steely determination. It is a constant process of refinement, where each client's programme is thoroughly researched and multiple design possibilities are explored through numerous drawings and mock-ups that test each alternative. Ideas are considered and discarded, rethought and reworked until only the essential qualities of a design remain. The result is an ingenious combination of structure and organisation, of logical purpose and precise beauty.

It may be tempting to consider Sejima and Nishizawa's refined compositions of lightness and transparency as elitist or quirky. However, their aesthetic is one of inclusion. Their approach is fresh, always offering new possibilities within the normal constraints of an architectural project that systematically takes the next step. They use common, everyday materials without losing sight of the possibilities of contemporary technology; their way of understanding space does not reproduce conventional models. They often opt for non-hierarchical spaces or, in their own words, for the "equivalence of spaces", creating democratic and unpretentious buildings according to the task and budget at hand. One example is the Almere project in the Netherlands, with its many simple classrooms and workshops, all with a privileged view of the sea. Another example is the Rolex Learning Centre in Lausanne, a space for student use day and night. Sejima and Nishizawa originally envisaged it as a multi-storey building, but during their deliberations they decided to make it a single but vast and fluid space. The building's many spaces (library, restaurant, exhibition areas, offices, etc.) are not differentiated by walls, but by the undulations of a continuous floor, which rises and falls to accommodate the different uses, while allowing views across this internal "landscape for people".

The relationship of the building to its context is of paramount importance to Sejima and Nishizawa. They have called public buildings "mountains in the landscape", believing that they should never lose their natural and meaningful connection to their surroundings. The New Museum of New York looks like a house in the bustling Bowery area of the city. Their glass museums, such as the Glass Pavilion at the Toledo Museum of Art (Ohio), blur the boundaries between indoors and outdoors, offering direct and changing views of the environment.

While Sejima and Nishizawa have not published theoretical treatises to date, they are brain architects, whose work is based on rigorous research and guided by solid and clearly defined concepts. As a tribute, Kazuyo Sejima was appointed director of the 2010 Venice Architecture Biennale.

The 2010 Pritzker Architecture Prize has been awarded to Kazuyo Sejima and Ryue Nishizawa for architecture that is both delicate and powerful, precise and fluid, ingenious but not overly or overtly clever; for creating buildings that successfully integrate with their contexts and the activities they contain, creating a sense of wholeness and experiential richness; for a singular architectural language that emerges from a collaborative process that is both unique and inspiring; for their outstanding completed buildings and the promise of new projects together.