The very nature of global sourcing means that components must carry clear and detailed specifications for material, heat treatment, and test methods. Qualified global heat treat facilities are capable of achieving good control of not only surface and gradient hardness, but also of microstructure, residual stress, and other critical metallurgical properties. To take full advantage of the heat treater’s capabilities, material specifications for heat treated components must have relatively tight control of chemistry, hardenability, and microcleanliness. Heat treat specifications similarly must require tight control of parameters such as surface, gradient, and core hardnesses. Surface microstructure including oxide networks, non martensitic transformation products, depth to first bainite, and others must also be specified. This paper will discuss some of the most critical metallurgical requirements and present guidelines for specification limits consistent with modern high quality heat treatment capabilities in the global heat treatment environment. Some guidelines concerning the supplier qualification process for heat treat shops will also be discussed.