  We report on measurements of branching fractions for several hadronic tau
decays to final states with kaons, which can be used to determine the strange
quark mass and the element |V_us| of the Cabibbo-Kobayashi-Maskawa quark-mixing
matrix. The results are obtained from data collected with the BaBar and Belle
detectors at the PEP-II and KEKB asymmetric-energy e+e- colliders at SLAC and
KEK, respectively, both operating at center-of-mass energies near the Y(4S)
resonance.
