Patriot Tower, Modernist skyscraper in City Center District, Dallas, US

One Dallas Center is a 30-story, 448-foot modernist skyscraper at 350 North St. Paul Street in downtown Dallas. Its diamond-shaped plan, designed by Henry N. Cobb of I.M. Pei & Partners, responds to the 30-degree angle where Live Oak Street meets the city grid. Two triangular notches on the sides create four extra corner offices per floor, and two-thirds of the facade is clad in aluminum rather than reflective glass.

Developer Vince Carrozza announced One Dallas Center in 1977 as phase one of a US$200 million three-building complex designed by I.M. Pei & Partners; only this tower was built. On October 11, 1978, a crane fell 27 stories from the roof, killing a worker and punching holes in the facade. The building opened in 1979, was renamed Patriot Tower in 2007, and was sold to Todd Interests in 2012.

The building's diamond footprint follows the 30-degree angle where Live Oak Street meets downtown's grid. Architect Henry N. Cobb of I.M. Pei & Partners set the tower back to leave green space at its entrances, and two triangular notches on its sides create four extra corner offices per floor. A permanent art collection inside includes works by Dallas artist JD Miller.

The building sits in the City Center District and is accessible via public transportation networks serving downtown Dallas. The mix of offices and residences creates varied activity throughout the day as workers and residents move through the space.

The building's diamond footprint follows the 30-degree angle where Live Oak Street meets downtown's grid. Two triangular notches on its sides create four extra corner offices per floor. The facade is two-thirds aluminum rather than reflective glass, with 2-inch stainless-steel projections separating metal from glass.