Title: Gibbsian and non-Gibbsian measures

Non-Gibbsian measures first appeared as an explanation for  the
"Renormalization Group peculiarities" which were discovered
more than twentyfive years ago by Griffiths and Pearce. Some of the 
questions they asked have been answered, but others   are still widely open.
The problems they raised have led to the study of non-Gibbsian states 
(probability measures). We discuss  some further related developments, 
in particular  applications to nonequilibrium questions and disordered 
models.