Interpretations of the NuTeV ${\sin }^2{\theta }_W$

We summarize theoretical explanations of the three $\sigma$ discrepancy between ${\sin }^2{\theta }_W$ measured by NuTeV and predicted by the Standard Model global fit. Possible new physics explanations ({\it e.g.} an unmized $Z^{\mathrm{\prime }}$) are not compelling. The discrepancy would be reduced by a positive momentum asymmetry $s^{-}$ in the strange sea; present experimental estimates of $s^{-}$ are unreliable or incomplete. Upgrading the NuTeV analysis to NLO would alleviate concerns that the discrepancy is a QCD effect.