2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44021The utility of precision electroweak measurements for predicting the Standard Model Higgs mass via quantum loop effects is discussed. Current constraints from $m_W$ and $\sinsthw\mzms$ imply a relatively light Higgs $\lsim 154$ GeV which is consistent with Supersymmetry expectations. The existence of Supersymmetry is further suggested by a discrepancy between experiment and theory for the muon anomalous magnetic moment. Constraints from precision studies on other types of ``New Physics'' are also briefly described.23 pages, no figures, Latex, Invited talks at SSI2004 SLAC SummerInstitute * In v2, only Ref. 20 expandedHigh Energy Physics - Phenomenologytext