HOK (firm)
 HOK (formerly Hellmuth Obata + Kassabaum) is a global design architecture engineering and planning firm. As of 2013 HOK is the largest U.S.-based architecture-engineering firm and the third-largest interior design firm. The firm maintains more than 1600 professional staff across a global network of 24 offices and is active in all major architectural specialties. Its senior leaders are located in several different locations across the world.