The specialized book "Multicomponent Media Based on Relaxor Ferroelectrics" offers a comprehensive analysis of the complex systems based on relaxor ferroelectrics. The authors, Inna Andrjushina and Larisa Reznichenko, present the results of their research, which includes both experimental and theoretical aspects. The work examines the stability intervals of perovskite-structured types in highly concentrated PZN systems and demonstrates how significant expansions can be achieved through the introduction of B-cations and the increase of merosity. Additionally, the microstructural properties of the solid solutions are characterized based on chemical composition and technological factors. The results are significant for understanding the physical properties of these materials and their application in various technological fields.