2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/39910Rare B decays of the type $b \to s~\ell^+\ell^-(ν\barν)$ are analyzed in a generic scenario where New Physics effects enter predominantly via $Z$ penguin contributions. We show that this possibility is both phenomenologically allowed and well motivated on theoretical grounds. The important role played in this context by the lepton forward-backward asymmetry in $B\to K^*\ell^+\ell^-$ is emphasized.4 pages, 1 figure, talk presented at ICHEP2000 (Osaka, Japan, July 27-Aug 2, 2000)High Energy Physics - Phenomenologytext