In an effort to control Nb segregation and Laves formation in Inconel 718 gas tungsten arc welds, transverse magnetic arc oscillation was employed. At optimum arc oscillation conditions, considerable fusion zone microstructural refinement and reduction in interdendritic Nb segregation were achieved, with consequent reduction in the amount of Laves phase and improvement in its morphology. These improvements in weld microstructure were shown to result in significant improvement in weld tensile and stress rupture properties in direct aged condition. Use of post-weld solution treatment improved the weld properties to some extent in both unoscillated and oscillated welds, but the oscillated welds maintained their superiority over unoscillated welds in post-weld solution treated and aged condition also.