In this chapter, we supplement the general fundamentals with some (essential) aspects that arise in magnetic confinement aimed at energy-producing nuclear fusion. Fusion in toroidal configurations such as the tokamak, stellarator, etc., is an important long-term physical and technical project that touches on many highly interesting areas of theoretical physics. Here, we address only a few of these. The selection criterion is the direct connection to the general fundamentals discussed in previous chapters. Therefore, some other important topics are left out. In this regard, we must refer to the specialized literature.