  In this talk I first discuss predictions based on QCD sum rules and on
hadronic models for the properties of vector mesons in the nuclear medium. I
then describe possible experimental signatures and show detailed predictions
for dilepton invariant mass spectra with a special emphasis on nuclear
reactions involving elementary incoming beams and nuclear targets. I will in
particular illustrate that the sensitivity of pion and photon induced reactions
to in-medium effects is nearly as large as that of heavy-ion reactions.
