  The strong "anomalous" J/Psi suppression observed recently by the NA50
Collaboration at CERN SPS has attracted considerable attention. Is it the first
signature of a long-awaited quark-gluon plasma, or just a peculiar combination
of "conventional" effects acting together to produce the puzzling pattern
observed experimentally? This talk is an attempt to summarize the theoretical
explanations proposed during the last two years.
