New piezoelectric materials have developed on the base of the crystal chemistry conceptions of increasing the piezoelectric activity of solid solutions in the morphotropic boundary region and on the base of conceptions about influence of the defect structure on the process of sintering of the ceramics. While studying the properties of the solid solutions in the system PbTiO3-Pb(Fe½Nb½)O3, the material with high piezoelectric activity (ε∼ 4 000, d31 ∼ 7 x 10-6 CGSE units, Kr ∼ 0,5) was obtained. The investigation of the influence of additives on the properties of the solid solutions PbTiO3-PbZrO3 made it possible to create a number of new materials with high properties (∼ 1 500, Kr ∼ 0,6, d31 ∼ 5 x 10-6 CGSE units, Qm ∼ 1 500). The distinguishing feature of the developed materials is low sintering temperature of ceramics (1 000-1 100 °C), which makes it possible to increase the range of its applications.