  In this paper we consider non-compact non-flat simply connected harmonic
manifolds. In particular, we show that the Martin boundary and Busemann
boundary coincide for such manifolds. For any finite volume quotient we show
that (up to scaling) there is a unique Patterson-Sullivan measure and this
measure coincides with the harmonic measure. As an application of these results
we prove that the geodesic flow on a non-flat finite volume harmonic manifold
without conjugate points is topologically transitive.
