  We review the theoretical status of b to s hadronic penguin decays in the
Standard Model and beyond. We summarize the main theoretical tools to compute
Branching Ratios and CP asymmetries for b to s penguin dominated nonleptonic
decays, and discuss the theoretical uncertainties in the prediction of
time-dependent CP asymmetries in this processes. We consider general aspects of
b to s transitions beyond the Standard Model. Then we present detailed
predictions in supersymmetric models with new sources of flavor and CP
violation.
