1. Introduction to theory session main issues to be discussed during this session

2.  dalitz decay in pp collisions inclusive (pp  e+e-+X)exclusive (pp  ppe+e-) How precise is the theory on  ->pe+e- decay? (talks: B.Ramstein/B.Martemyanov) Can we extract from these data form-factors, Branching Ratio? HADES data & PLUTO Preliminary

3.  dalitz decay in HI collisions HSD E. Bratkovskaya What is the mechanism which makes  spectrum hard? mass dependent BR  Ne+e- ? How well do we know it? How well do we know spectral function of  in nuclear matter? Transport : E. Bratkovskaya, E. Santini, G. Wolf (after coffee break)

4. p-n bremsstrahlung Kaptari & Kampfer HADES data & PLUTO Preliminary Do we understand relevant processes for dielectron production in p-n, in particular bremsstrahlung ? (B. Kampfer, G. Lykasov) Does it really explain HI data?

5. Vector meson spectral function D. Schumacher et.al (UrQMD) Still no medium effects involved ! SIS18 SPS (  +  -  e+e-) What is the vacuum spectral function of the rho meson at SIS18? E. Santini/B. Martemyanov 2m 