Hellmuth, Obata & Kassabaum

HOK (formerly called Hellmuth, Obata + Kassabaum) is a global architectural, interior design, engineering, planning and consulting firm. HOK is the largest architectural-engineering group based in the United States and one of the leaders in sustainable and high-performance design.The firm has more than 1,700 professional employees in its 25 offices around the world and works in virtually all major architectural specialties. Tokyo Telecom Center in Tokyo, building designed by the firm.

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