  The problem of a weak shock, reflected and diffracted by a wedge, is studied
for the two-dimensional compressible Euler system. Some recent developments are
overviewed and a perspective is presented within the context of a real gas,
modeled by the van der Waals equation of state. The regular reflection
configuration and the detachment criterion are studied in the light of real gas
effects. Some basic features of the phenomenon and the nature of the
self-similar flow pattern are explored using asymptotic expansions. The
analysis presented here predicts several inviscid flow properties of the real
gases undergoing shock reflection-diffraction phenomenon.
