Phase structure of strongly interacting matter

We discuss an effective chiral SU(3) model that includes hadronic as well as quark degrees of freedom. Whereas the expectation values of the scalar mesonic fields correspond to the order parameter of chiral symmetry restoration a field representi ng the Polyakov loop describes the deconfinement process. Excluded volume effects for the hadr ons are taken into account. We present numerical results for zero chemical potential. Comparisons to lattice results are shown.