THE PUBLISHED ISOTHERMAL TRANSFORMATION and continuous cooling transformation diagrams for the standard steel grades are extremely useful in understanding the capabilities of these materials, and should be considered in conjunction with the published hardenability data, such as that included in ASTM Specification A 914/A 914M, Steel Bars Subject to Restricted End-Quench Hardenability Requirements, when setting up a heat treatment cycle. The emphasis in this chapter is on techniques and equipment.