eff   
        sin**2 theta     from  measurements at the Z pole
                     lep
        ================================================= 



     Pierre Antilogus, DELPHI collaboration, IPN Lyon
 

 
Abstract:
--------- 
The results collected in the electroweak sector over the last years
end up to interesting limits on the Higgs mass. The main constraint 
comes from the value of sin**2 theta_eff derived from measurements at
the Z pole. In this presentation the experimental results contributing to
sin**2 theta_eff will be reviewed, with an emphasis on one of the two
dominant contributions : the measurements of the b quark Forward Backward
asymmetry (AFBbb) at LEP. The sources of potential problems and 
the corresponding solutions adopted in different AFBbb analyses will 
be underlined.