  Recent developments in the evaluation of vector-meson spectral functions in
hot and dense matter are discussed with emphasis on connections to the chiral
phase transition in QCD. Model independent approaches including chiral
low-density expansions, lattice QCD, chiral and QCD sum rules are put into
context with model predictions for in-medium vector-spectral function utilizing
effective Lagrangians. Hadronic many-body calculations predict a strong
broadening (and little mass shift) of the $\rho$ spectral function which
rapidly increases close to the expected phase boundary of hadronic and
quark-gluon matter. Pertinent dilepton rates appear to degenerate with
perturbative quark-antiquark annihilation in the Quark-Gluon Plasma, suggestive
for chiral symmetry restoration. Applications to low-mass dilepton spectra in
heavy-ion collisions result in quantitative agreement with recent high-quality
data at the CERN-SPS. Thermal radiation from temperatures around $T_c$
consistently reproduces the experimental dilepton excess observed at masses
above 1 GeV as well. The interpretation of dilepton sources at high transverse
momentum appears to be more involved.
