The first U.S. Verification Model (V-Model) appeared in a proposal from Hughes Aircraft in 1982 for the U.S. Federal Aviation Administration’s advanced automation system program. From the V-Model came our current conceptions of allocation, validation, and verification. Allocation assigns product requirements to systems and subsystems. Validation assures that the configuration was built to the engineering aka did we build it right. Verification assures all allocated requirements of a configuration have been met aka did we build the right thing.