And in this document, NASA has provided guidance. Quite a lot of it. Requirements are the key element of a NASA planning document like this, the bureaucratic currency by which NASA buys off on the safety of a spacecraft, such as the amount of habitable volume the agency requires. Generally companies prefer fewer requirements as it allows them more freedom for design and innovation. More requirements give NASA engineers more control over the design of vehicles. Several of the companies were shocked by the number of requirements levied in the NASA documents. One participant estimated there are more than 3,000 requirements. The companies were hoping for hundreds. Some of the requirements do seem fairly harsh. For example, on page 50 of the 246-page “contract data requirements list,” it appear