Paragon Space Development Corporation is an American company headquartered in Tucson, Arizona. Paragon is a provider of environmental controls for extreme and hazardous environments. They design, build, test and operate life-support systems and leading thermal-control products for astronauts, contaminated water divers, and other extreme environment explorers, as well as for uncrewed space and terrestrial applications.

Development of the Commercial Crew Program began in the second round of the Commercial Crew Development (CCDev) program, which was rescoped from a technology development program for human spaceflight to a competitive development program that would produce the spacecraft to be used in the Commercial Crew Program to provide crew transportation services to and from the International Space Station (ISS). To implement the program NASA awarded a series of competitive fixed-price contracts to private vendors starting in 2011. Operational contracts to fly astronauts were awarded in September 2014 to SpaceX and Boeing, and NASA expected each company to complete development and achieve crew rating in 2017. Each company performed an uncrewed orbital test flight in 2019. SpaceX operational flights started in November 2020.