Polymer systems with intra and/or interchain bridge bonds of various types (covalent, electrostatic, coordination, etc.) have drawn the attention of numerous researchers for many years. A considerable interes in crosslinked polymers is due to the fact that when their topological structure is varied, they can acquire quite different properties; they can be soluble or lose solubility, exibiting a certain extent of swelling capacity. Their physicomechanical properties can also change drastically in the condensed state. The specific propertieis displayed by polymers with bridge bonds extend the possibilities and prospects of using polymer systems in technology, medicine, biotechnology, and agriculture (as construction materials, polymer glasses with high mechanical strength and high thermal stability, rubbers, ion-exchange resins and sorbents, immobilizing media for the stabilization of natural and synthetic catalysts, insoluble polymer reagents which are used, for instance, in peptide synthesis, therapeutic preparations based on modified enzymes, hydrogels with a high degree of swellin, et.). On the other hand, crosslinked polymer systems serve to develop new promising trends in the investigation of chemical, physical, physicochemical, and mechanical properties of polymers.