PbMoO4:Nd3+ and PbWO4:Nd3+ single crystals were grown by the Czochralski method. The Nd3+ doping was performed by means of isostructural and non-isostructural compounds. Co-doping was also used. The spectral-kinetic characteristics of PbMoO4:Nd3+ and PbWO4:Nd3+ crystals were studied. Dielectric measurements were carried out at various temperatures ranging from 100 to 500 degrees C and at various frequencies ranging from 25 Hz to 1 MHz using the parallel plate capacitor method. Parameters of the dielectric relaxation process are determined. The possible mechanism of charge compensation is discussed. (C) 2010 Elsevier B.V. All rights reserved.