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We present a new determination of fDs using 5 million e+e- → cc̅ events obtained with the CLEO II detector. Our value is derived from our new measured ratio Γ(Ds+ → μ+ν)/Γ(Ds+ → φ π +) = 0.173±0.023 ±0.035. Using Ɓ(Ds+ → φ π +) = (3.6±0.9)%, we extract fDs = (280±19±28±34) MeV. We compare this result with various model calculations.