The BaZrO3 and Ta have been used to improve piezoelectric properties of (K, Na)NbO3 ceramics by the construction of the phase boundary, and (1 - x)K0.48Na0.52(Nb0.95Ta0.05)O-3-xBaZrO(3) [(1 - x) KNNT-xBZ] ceramics were prepared by the conventional solid-state method. The effect of BZ content on their phase structure, microstructure, and electrical properties has been investigated. A rhombohedral and orthorhombic phase coexistence has been observed in the compositional range of 0.05 <= x <= 0.07. With increasing BZ content, their T-c and To-t values decrease gradually, and the dielectric constant increases linearly. The ceramic with x = 0.06 exhibits an enhanced piezoelectric behavior (d(33) similar to 193 pC/N and k(p) similar to 32.6%) because of the coexistence of two phases together with a dense microstructure. As a result, the construction of a rhombohedral and orthorhombic phase boundary is an effective way to improve the piezoelectric properties of KNN-based ceramics. (C) 2013 Elsevier B.V. All rights reserved.