OTRAG (German: Orbital Transport und Raketen AG, or Orbital Transport and Rockets, Inc.), was a German company based in Stuttgart, which planned in the late 1970s and early 1980s to develop an alternative propulsion system for rockets. OTRAG was the first commercial developer and producer of space launch vehicles. The OTRAG Rocket claimed to present an inexpensive alternative to existing launch systems through mass-production of Common Rocket Propulsion Units (CRPU).