This specification will apply to complex supplies, components, equipments and systems for which the requirements of MIL-I-45208 are inadequate to provide needed quality assurance. In such cases, total conformance to contract requirements cannot be obtained effectively and economically solely by controlling inspection and testing. Therefore, it is essential to control work operations and manufacturing processes as well as inspections and tests. The purpose of this control is not only to assure that particular units of hardware conform to contractual requirements, but also to assure interface compatibility among these units of hardware when they collectively comprise major equipments, sub-systems and systems.

Paragraph 8 of MIL-Q-9858A is, in essence, a summary of this handbook's discussion of Section 1 of the specification. Two points of that discussion bear repeating:

1. The contract and only the contract states which specification--MIL-Q-9858A or MIL-I-45208A--must be followed by the contractor as a minimum.

2. MIL-Q-9858A is intended primarily for the manufacture of complex equipment; MIL-I-45208A primarily for simple items.