  Hadronic tau decay precision data are analyzed with account of both
perturbative and power corrections of high orders within QCD. It is found that
contributions of high order power corrections are essential for extracting a
numerical value for the strange quark mass from the data on Cabibbo suppressed
tau decays. We show that with inclusion of new five-loop perturbative
corrections in the analysis the convergence of perturbation theory remains
acceptable only for few low order moments. We obtain m_s(M_\tau) =130\pm 27 MeV
in agreement with previous estimates.

High Energy Physics - Phenomenology