The relaxor-type behavior, electrical polarization buildup, and switching in 0.92Pb(Zn(1/3)Nb(2/3))O(3)-0.08PbTiO(3) nanostructured ceramics with a grain size of approximately 20 nm is reported for the first time. This composition presents the highest-known piezoelectric coefficients, yet phase stability is an issue. Ceramics can only be obtained by the combination of mechanosynthesis and spark-plasma sintering. The results raise the possibility of using nanoscale, perovskite-relaxor-based morphotropic-phase-boundary materials for sensing and actuation in nanoelectromechanical systems.