To a large extent, the induction coil and its coupling to the workpiece determine the precise heating pattern that is developed. However, it is often desirable to modify this pattern in order to produce a special heating distribution or to increase energy efficiency. At other times, the high heating rates of induction are needed for processing nonconductors. This chapter describes broad methods of accomplishing such objectives: modification of the field of magnetic induction, use of devices to prevent auxiliary equipment or certain portions of a workpiece from being heated, and techniques to apply heating to electrically nonconductive materials. These methods make use of devices such as flux concentrators, shields, and susceptors. The chapter provides a description of the materials for these devices and guidelines for their application.