Dielectrics.- A. Introduction.- B. The static dielectric constant.- C. Behavior at optical frequencies.- D. Dielectric loss.- E. Methods of measurement.- F. Relation of dipole moments to molecular structure.- Dielektrischer Durchschlag.- A. Historischer Überblick.- B. Wärmedurchschlag.- C. Rein elektrischer Durchschlag.- Literatur.- Piezoelectricity Electrostriction and Ferroelectricity.- A. General introduction.- B. Piezoelectricity.- C. Piezoelectricity and electrostriction as tensors.- D. Changes of phase and crystal symmetry.- E. Macroscopic description of ferroelectricity and antiferroelectricity.- F. Thermodynamics and phenomenological theory.- G. Statistical atomic theories of ferroelectricity.- General references.- Sachverzeichnis (Deutsch-Englisch).- Subject Index (English-German).