  The penguin mediated processes $b\rightarrow s g$ and $b\rightarrow s l^+l^-$
are studied. In the Standard Model, for the leptonic modes improvement in
experimental limits will put strigient bounds on the top mass, where the
present limit from $b\rightarrow s \mu^+\mu^-$ is 390 GeV. For hadronic penguin
processes, although the gluonic penguin dominates, we find the electroweak
contribution are around 30\% for the upper range allowed top mass. The
branching ratio for $B\rightarrow X_s \phi$ is predicted to be in the range
$(0.6\sim 2)\times 10^{-4}$. Effects of the charged Higgs in two Higgs doublet
models are discussed.

High Energy Physics - Phenomenology