Review of the tau polarisation in Z decays at LEP using tau hadronic decay channels

The measurements of the tau polarisation at LEP, using hadronic decay channels are reviewed. These decay channels carry about 80% of the weight in the LEP average. The τ→hντ, τ→ρντ a nd τ→a1ντ decay channels are used by each experiment. Advantages and problems for each channel are reviewed. The reconstruction of photons and the charged track identification are the tools needed to classify the decay channel. The measurements are essentially uncorrelated between experiments, and the Aτ and Ae are in good agreement between the different channels and experiments. Finally, the progress since the Montreux workshop is summarised and possible improvements for the final LEP measurements are reviewed. (orig.)