**Abstract**

This chapter deals with the description of recent research activities oriented on the perspective of microwave technologies in medicine and biology. It brings new ideas about the possibilities of using microwaves in thermotherapy—above all toward hyperthermia in cancer treatment. Development of new types of hyperthermia applicators (based, e.g., on technologies such as metamaterials, evanescent modes in waveguides, and other types of transmission structures) will be discussed here. Furthermore, we would like to underline in this chapter perspectives of microwaves in medical diagnostics. It is possible to expect that, e.g., microwave differential tomography, UWB radar, and microwave radiometers (all three can be used both for medical diagnostic and for noninvasive temperature measurement) will soon play an important role in it. Finally, experimental equipment necessary for research on the biological effects of EM fields is presented.

**Keywords:** microwave thermotherapy, hyperthermia in cancer treatment, microwave medical diagnostics, noninvasive temperature measurement, microwave differential tomography, UWB radar in medical diagnostics
