  A mean field theory of the localization transition for bosonic systems is
developed. Localization is shown to be sensitive to the distribution of the
random site energies. It occurs in the presence of a triangular distribution,
but not a uniform one. The inverse participation ratio, the single site Green's
function, the superfluid order parameter and the corresponding susceptibility
are calculated, and the appropriate exponents determined. All of these
quantities indicate the presence of a new phase, which can be identified as the
{\it Bose-glass}.
