$\sin^{2} \theta_{w}$ Effectif From Hadronic Final States

The different techniques used to access sin 2 θ eff lep in the hadronic sector is presented with a summary of the results obtained by the LEP experiments. The LEPI average in this sector is sin 2 θ eff lep = 0.23225 ± 0.00035. The main sources of uncertainties in the experimental measurements are reviewed with a special attention to the forward backward b asymmetry.