The multinational company IAE International Aero Engines AG brings together four of the finest aircraft engine manufacturers in the world. Besides representing the "best of the best" aerospace technology available, the partner companies represent four countries and three continents. Each IAE partner contributes an individual module to the V2500 engine, an arrangement that enables each partner's engineers to focus their attention on continuously refining that module. Pratt & Whitney produces the combustor and high-pressure turbine, Rolls-Royce the high-pressure compressor, JAEC the fan and low-pressure compressor and MTU the low-pressure turbine. Pratt & Whitney and Rolls-Royce assemble and test the engines at their respective facilities, and a headquarters staff seconded from partner companies are responsible for the sales, marketing, support and administration of the program.