Neodymium doped YVO(4) is becoming an increasingly popular material for solid state lasers. Among the advantages of vanadates over more traditional materials are that the absorption cross section at 808 nm is significantly larger, the emission cross sections are higher, leading to lower lasing thresholds, and the bandwidth for pump absorption is higher. We report new measurements of the refractive index and thermo-optic coefficient of this material that will aid in the design of laser cavities and other nonlinear optical elements.