Since the early 1960s, DWL has played a leading role in the development of Phoenix Sky Harbor International Airport, providing architectural and planning services that have grown the facility from one terminal to three. Early projects at the Airport include the design of Terminal 2 (in association with Lescher & Mahoney, 1962); Terminal 3 (1979), which is currently undergoing a complete renovation; and Terminal 4 (1990), the largest structural capital improvement project in Phoenix at the time.