We have studied the third order optical nonlinearities of Ge-As-Se-based glasses. The glasses have high melting and glass transition temperatures that offer the potential for integration with traditional compound oxide glasses into highly nonlinear, high-index-contrast fibers. We used z-scan and femtosecond pump-probe techniques to measure the nonlinear refractive index and two-photon absorption coefficient of the glasses at telecommunication wavelengths. Nonlinearities as high as similar to900x that of silica were measured at 1540 nm in Ge35As15Se50 with a glass transition temperature of 380 degreesC. (C) 2004 American Institute of Physics.