In August 1993, NASA selected Boeing as prime contractor for the International Space Station, a permanent orbiting laboratory in space and the largest international space venture ever undertaken. With a "space footprint" the size of two football fields, the space station averages an altitude of 220 statute miles. As the prime contractor, Boeing is responsible for design, development, construction and integration of the ISS and assisting NASA in operating the orbital outpost. Boeing built all of the major U.S. elements. In addition, Boeing oversees thousands of subcontractors around the globe and works with 16 international partners on the project.