Commercial Orbital Transportation Services (COTS) is a NASA program to coordinate the delivery of crew and cargo to the International Space Station by private companies.
The program was announced on January 18, 2006. NASA has suggested that "Commercial services to ISS will be necessary through at least 2015."
COTS must be distinguished from the related Commercial Resupply Services (CRS) program. COTS relates to the development of the vehicles, CRS to the actual deliveries. COTS involves a number of Space Act Agreements, with NASA providing milestone-based payments. COTS does not involve binding contracts.