  The description of excitations in hot and dense (hadronic) matter is
discussed with emphasis on the use of correlation functions as a common
framework for comparing different model (and QCD lattice) calculations with
each other. Typical regimes of applicability of hadronic approaches are
assessed, together with possibilities to confront them with experiment. We also
elaborate on recent developments to relate baryonic in-medium effects to chiral
symmetry restoration.
