High energy density ceramic capacitors with temperature stable permittivity across -150°C to 300°C are desired for a wide variety of electronic devices. Traditional dielectrics such as barium titanate provide a high permittivity but that permittivity is strongly temperature dependent over this specified temperature range. The goal of this work is to create a perovskite material that has a high levels of B site cation disorder to take advantage of a relaxor dielectric mechanism that helps realize temperature stable dielectric properties. Perovskite ceramic solid solutions were synthesized from oxide and carbonate precursors and calcined in air at temperatures ranging from 900 to 1050°C and sintered in air at temperatures ranging from 1050 to 1200°C. Initial results focus on the BaTiO3-Bi(Zn1/2Ti1/2)O3- La(Mg1/2Ti1/2)O3 ternary system and show a minimal temperature dependence with a temperature coefficient of permittivity (TC ) as low as -136.5 ppm/°C. However, the low permittivity values for these compounds motivated the inclusion of Pb(Ni1/3Nb2/3)O3, a perovskite with high relative permittivity and a low temperature of maximum permittivity (Tmax). The phase structure and dielectric properties of compositions based on the compound BaTiO3-Bi(Zn1/2Ti1/2)O3 along with additives La(Zn1/2Ti1/2)O3 and Pb(Ni1/3Nb2/3)O3 were investigated by X-ray diffraction and dielectric measurements. Results of this quaternary system show a sufficient maximum permittivity but a large TC ppm/°C. Future work involves compositional modifications aimed at increasing the relative permittivity while optimizing compositional end members that enable the TC to be near zero.