Lead-free (K0.5Na0.5)NbO3 (KNN) piezoelectric ceramics doped with different amounts of GeO2 were prepared and characterized. GeO2 was found to effectively improve the sinterability and piezoelectric properties of the material. The improvement in the sinterability is ascribed to the formation of a liquid phase, which decreased the sintering temperature from 1080 degrees C to 1010 degrees C. The improvement in the properties is attributed to the replacement of Nb5+ with Ge4+ to form acceptor dopants. The following optimized properties were obtained from the KNN ceramic with 0.75 wt% GeO2: piezoelectric constant (d(33)) = 126 pC/N, planar electromechanical coupling coefficient (k(p)) = 42.8%, mechanical quality factor (Q(m)) = 140, and dielectric loss (tan) = 3.8%.