PORTLAND - Pietro Belluschi, an internationally renowned architect who ushered in a new era of high-rise building design and helped design several Seattle buildings, including the Washington State Convention and Trade Center, died Monday at his home. He was 94.

Mr. Belluschi was best known for his design of the Commonwealth Building in downtown Portland. Completed in 1948, it was the first curtain-glass-and-aluminum high-rise and heralded a wave of similar modern buildings around the world.

In Seattle, Mr. Belluschi was the design consultant on the trade center, a project he found challenging. In 1983, he said of the building, "in 60 years as an architect and 32 years working with many urban-renewal problems, I have never been exposed to a more interesting or a more difficult project than this. And I have never seen a more brilliant solution than this."

Mr. Belluschi did consulting work in the 1960s for the University of Washington and later for the Seafirst "black box" building downtown, the Downtown Library building and the Stimson Center, which later became the Pacific First Centre.

Mr. Belluschi also collaborated on the design of St. Mary's Cathedral and the Bank of America World Center, both in San Francisco, and the Pan-Am Building and the Juilliard School of Music, both in New York City.

"He never followed any kind of formula," said Eduardo Catalano, a professor emeritus of architecture at the Massachusetts Institute of Technology. "His architecture encompassed both the formality and randomness of life. He touched the sky with his feet on the earth."

In 1991 Mr. Belluschi was awarded the National Medal of Arts, the second architect to receive the award. In 1972 the American Institute of Architects gave him its highest honor, the Gold Medal.

Born in 1899 in Ancona, Italy, he served with the Italian army in World War I. He received an engineering degree from the University of Rome in 1922.

A year later Mr. Belluschi came to the United States, speaking no English. He was an exchange student at Cornell University, where he eventually earned a degree in civil engineering.

"Coming to America changed my life to a greater extent than I thought possible," he said. "From a dreamy, lazy boy, I became almost overnight an aggressive and determined man - determined to succeed at all costs as a student, as a person and as an architect."

Seattle Times staff reporter Dave Birkland contributed to this report.