HNTB Architecture offers a range of buildings services to clients in the aviation, corporate, education, federal and local government markets. The company specializes in historic preservation, program management and structural engineering work. It has worked on several projects, such as Tucson International Airport Expansion, Kansas City Public Library and Arthur Anderson. The company is a part of HNTB Companies, which is one of the leading design and planning firms in the United States. It operates through three operating units. The company s HNTB Corporation offers a variety of transportation services. Its another unit, HNTB Federal Services Corporation, specializes in engineering, architectural, planning and construction management.