What was the structure of NASA's Commercial Crew and Cargo programs for acquiring services?

NASA offered fixed-price contracts for companies to develop systems and then purchased transport services.

The relationship between NASA and commercial providers was formalized through programs like the Commercial Crew Program (CCP) and Commercial Resupply Services (CRS). This represented a deliberate policy pivot away from the historical model where the government funded and owned the vehicle development entirely. Instead, NASA shifted the financial risk and management responsibility for development schedules onto the private contractors by offering fixed-price contracts. Under this structure, the commercial entity developed the transportation system at its own financial risk, and NASA then functioned as a customer purchasing the resultant service, such as crew transport or cargo delivery, only upon certification and delivery.