The observed pattern of neutrino mixing may be the result of a 2-3( μ- τ) symmetry in the leptonic sector. We consider a two Higgs doublet model with a 2-3 symmetry in the down type quark and the charged lepton sector. The breaking of the 2-3 symmetry by the strange quark mass and the muon mass leads to FCNC in the quark sector and the charged lepton sector that are suppressed by m_s m_b and m_μ m_τ in addition to the mass of the heavy Higgs boson of the second Higgs doublet. A Higgs boson mass

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... of m_H ∼ 600 - 900 GeV can explain the deviation from standard model reported in several rare B decays. Predictions for other B decays are made and a new CP phase is predicted in B_s-B̅_s mixing. The lepton flavour violating decays τ→μl̅(q̅) l(q) are below the experimental limits. The breaking of 2-3 symmetry in the lepton sector can lead to deviations of the atmospheric neutrino mixing angle from the maximal value by ∼ 2 degrees.