The b quark forward-backward asymmetry has been measured using the entire
OPAL $\rm Z^0$ hadronic decay sample. $\rm Z\rightarrow b\bar{b}$ decays
were selected using a combination of secondary vertex and lepton tags,
and the sign of the b quark charge was determined using an inclusive
tag based on jet, vertex and kaon charges. Within the
framework of the Standard Model, the  result is interpreted as a measurement
of the effective weak mixing angle $\rm\sin^2\theta_W^{eff,e}$.