Measurement of the inclusive semileptonic b branching ratios and the extraction of |Vcb| at LEP

The inclusive direct b --> l(-) and cascade b --> c --> l(+) semileptonic branching ratios of the b quark were measured by the four LEP collaborations by means of several strategies. The first inclusive measurement of BR(b --> (c) over bar --> l(-)) was obtained by DELPHI. From the BR(b --> l(-)) LEP average, the most precise determination of the \V-cb\ coupling constant was then extracted in the OPE approach.